Showing posts with label Dietary Supplements. Show all posts
Showing posts with label Dietary Supplements. Show all posts

June 19, 2014

Liver dangers from herbal supplements, OTC and RX drugs, new guidelines warn

Provided by ScienceDaily

Date: June 17, 2014

Source: American College of Gastroenterology (ACG)

Summary: New clinical guidelines on the diagnosis and management of idiosyncratic drug-induced liver injury (DILI) have now been released. DILI is a rare adverse drug reaction, challenging to diagnose, and can lead to jaundice, liver failure and even death. The frequency of DILI incidence is increasing, as the use of herbal and dietary supplements has drastically increased over the last 10 years.

New clinical guidelines on the diagnosis and management of idiosyncratic drug-induced liver injury (DILI) appear in the July issue of The American Journal of Gastroenterology. DILI is a rare adverse drug reaction, challenging to diagnose, and can lead to jaundice, liver failure and even death. The frequency of DILI incidence is increasing, as the use of herbal and dietary supplements has drastically increased over the last 10 years.

The new guidelines from the American College of Gastroenterology, intended for use by physician and other health-care providers, include an overview of risk factors, diagnosis evaluation and causality assessment, prognosis factors, and management of hepatotoxicity due to pre-existing chronic liver disease or herbal/dietary supplement intake. One of the key focuses of the guidelines is on herbal and dietary supplements, which many doctors warn should be used with caution.

"A lot of consumers have a preconceived notion that if it's a natural product, it must be safe. But that is not necessarily the case," said Herbert Bonkovsky, MD, FACG, co-author of the guidelines. "Most of these products are not well-regulated and have very little oversight. Traces of heavy metals and prescription drugs have even been found in some herbal and dietary supplements. We encourage patients to talk to their doctor about all medications they are taking, and herbal and dietary supplements should be no exception."

The guidelines include a table of the most common over-the-counter and prescription drugs and supplements that cause DILI, and their usual patterns of liver injury. The table lists antibiotics (amoxicillin/clavulanate is the most commonly associated with DILI) and herbal and dietary supplements.

Of the herbal and dietary supplements, green tea extract tops the list as one of the most common dietary supplements associate with DILI injury. To give context, Dr. Bonkovsky says that the average cup of green tea has around 50-150 mgs of catechins, a group of polyphenols that are the major active ingredients. In some green tea extract pills, known to help with weight loss and other factors, the levels of such catechins can be over 700 mg. This can be particularly dangerous when the pills are taken multiple times a day.

It is important to note that DILI remains a "diagnosis of exclusion," which underscores the importance of patients giving their doctors a full history of all medications and supplement use. "Accurate history of medication exposure and onset and course of liver biochemistry abnormalities is crucial," says lead guideline author Naga P. Chalasani, MD, FACG.

Story Source:

The above story is based on materials provided by American College of Gastroenterology (ACG). Note: Materials may be edited for content and length.

Journal Reference:

  1. Naga P Chalasani, Paul H Hayashi, Herbert L Bonkovsky, Victor J Navarro, William M Lee, Robert J Fontana. ACG Clinical Guideline: The Diagnosis and Management of Idiosyncratic Drug-Induced Liver Injury. The American Journal of Gastroenterology, 2014; DOI: 10.1038/ajg.2014.131

Source

Also See: Drug-Induced Liver Injury Guidelines Released by ACG

September 1, 2013

Hepatitis C: A Focus on Dietary Supplements

Provided by NIH - National Center for Complementary and Alternative Medicine (NCCAM)

Get The Facts

Introduction

Hepatitis C is a liver disease caused by a virus. It is usually chronic (long-lasting), but most people do not have any symptoms until the virus causes liver damage, which can take 10 or more years to happen. Without medical treatment, chronic hepatitis C can eventually cause liver cancer or liver failure. Conventional medical treatments are available for chronic hepatitis C. Some people with hepatitis C also try complementary health approaches, especially dietary supplements. This fact sheet provides basic information on hepatitis C, summarizes scientific research on selected supplements, and suggests sources for additional information.

Key Points

  • Are Dietary Supplements for Hepatitis C Safe?
    • Colloidal silver is not safe; it can cause irreversible side effects.
    • Data on the safety of other supplements is limited. However, some can have side effects or may interact in harmful ways with medications, and some may be unsafe for people with certain health problems.
    • If you have hepatitis C, check with your health care provider before using any dietary supplement to make sure that it is safe for you and compatible with any medical treatment that you are receiving for hepatitis C or any other health problem.
  • Are Dietary Supplements for Hepatitis C Effective?
    • No dietary supplement has been shown to be effective for hepatitis C or its complications.
    • The results of research supported by the National Center for Complementary and Alternative Medicine (NCCAM) and National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) have shown that silymarin, the active extract of milk thistle and the most popular complementary health product taken by people with liver disease, was no more effective than placebo in people with hepatitis C.
    • Research on other dietary supplements for hepatitis C, such as zinc, licorice root (or its extract glycyrrhizin), S-adenosyl-L-methionine (SAMe), and lactoferrin, is in its early stages, and no firm conclusions can be reached about the potential effectiveness of these supplements.

Keep in Mind

  • It is important not to replace conventional medical therapy for hepatitis C with dietary supplements or other approaches that have not been shown to be effective.
  • Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

About Hepatitis C

Hepatitis C, a contagious liver disease, is caused by the hepatitis C virus. People can get hepatitis C through contact with blood from a person who is already infected or, less commonly, through having sex with an infected person. The infection usually becomes chronic. Chronic hepatitis C often is treated with drugs that can eliminate the virus. This may slow or stop liver damage, but the drugs may cause side effects, and for some people, treatment is ineffective. An estimated 3.2 million Americans have chronic hepatitis C. To learn more about hepatitis C, visit the NIDDK Web site.

Use of Herbal Supplements and Other Complementary Approaches for Hepatitis C

Several herbal supplements have been studied for hepatitis C, and substantial numbers of people with hepatitis C have tried herbal supplements. For example, a survey of 1,145 participants in the HALT-C (Hepatitis C Antiviral Long-Term Treatment Against Cirrhosis) trial, a study supported by the National Institutes of Health (NIH), found that 23 percent of the participants were using herbal products. Although participants reported using many different herbal products, silymarin (milk thistle) was by far the most common. Another study, which surveyed 120 adults with hepatitis C, found that many used a variety of complementary health approaches, including multivitamins, herbal remedies, massage, deep breathing exercises, meditation, progressive relaxation, and yoga.

What the Science Says

No dietary supplement has been shown to be effective for hepatitis C. This section summarizes what is known about the safety and effectiveness of milk thistle and some of the other dietary supplements studied for hepatitis C.

  • Milk thistle (scientific name Silybum marianum) is a plant from the aster family. Silymarin is an active component of milk thistle believed to be responsible for the herb’s health-related properties. Milk thistle has been used in Europe for treating liver disease and jaundice since the 16th century. In the United States, silymarin is the most popular dietary supplement taken by people with liver disease. However, two rigorously designed studies of silymarin in people with hepatitis C did not show any benefit.
    • A 2012 controlled clinical trial, cofunded by NCCAM and NIDDK, showed that two higher-than-usual doses of silymarin were no better than placebo in reducing the high blood levels of an enzyme that indicates liver damage. In the study, 154 people who had not responded to standard antiviral treatment for chronic hepatitis C were randomly assigned to receive 420 mg of silymarin, 700 mg of silymarin, or placebo three times per day for 24 weeks. At the end of the treatment period, blood levels of the enzyme were similar in all three groups.
    • Results of the HALT-C study mentioned above suggested that silymarin use by hepatitis C patients was associated with fewer and milder symptoms of liver disease and somewhat better quality of life, but there was no change in virus activity or liver inflammation. The researchers emphasized that this was a retrospective study (one that examined the medical and lifestyle histories of the participants). Its finding of improved quality of life in patients taking silymarin was not confirmed in the more rigorous 2012 study described above.

Safety. Available evidence from clinical trials in people with liver disease suggests that milk thistle is generally well-tolerated. Side effects can include a laxative effect, nausea, diarrhea, abdominal bloating and pain, and occasional allergic reactions. In NIH-funded studies of silymarin in people with hepatitis C that were completed in 2010 and 2012, the frequency of side effects was similar in people taking silymarin and those taking placebos. However, these studies were not large enough to show with certainty that silymarin is safe for people with chronic hepatitis C.

Other supplements have been studied for hepatitis C, but overall, no benefits have been clearly demonstrated. These supplements include the following:

  • Probiotics are live microorganisms that are intended to have a health benefit when consumed. Research hasn’t produced any clear evidence that probiotics are helpful in people with hepatitis C. Most people can use probiotics without experiencing any side effects—or with only mild gastrointestinal side effects such as intestinal gas—but there have been some case reports of serious adverse effects in people with underlying serious health conditions.
  • Preliminary studies, most of which were conducted outside the United States, have examined the use of zinc for hepatitis C. Zinc supplements might help to correct zinc deficiencies associated with hepatitis C or reduce some symptoms, but the evidence for these possible benefits is limited. Zinc is generally considered to be safe when used appropriately, but it can be toxic if taken in excessive amounts.
  • A few preliminary studies have looked at the effects of combining supplements such as lactoferrin, SAMe, or zinc with conventional drug therapy for hepatitis C. The evidence is not sufficient to draw clear conclusions about benefit or safety.
  • Glycyrrhizin—a compound found in licorice root—has been tested in a few clinical trials in hepatitis C patients, but there is currently not enough evidence to determine if it is helpful. In large amounts, glycyrrhizin or licorice can be dangerous in people with a history of hypertension (high blood pressure), kidney failure, or cardiovascular diseases.
  • Preliminary studies have examined the potential of the following products for treating chronic hepatitis C: TJ-108 (a mixture of herbs used in Japanese Kampo medicine), schisandra, oxymatrine (an extract from the sophora root), and thymus extract. The limited research on these products has not produced convincing evidence that they are helpful for hepatitis C.
  • Colloidal silver has been suggested as a treatment for hepatitis C, but there is currently no research to support its use for this purpose. Colloidal silver is known to cause serious side effects, including a permanent bluish discoloration of the skin called argyria (for more information, see the NCCAM fact sheet Colloidal Silver.

NCCAM-Funded Research

NCCAM-supported research includes projects studying:

  • Herbal combinations for boosting antioxidant activity to treat liver disease
  • Potential drugs for treating hepatitis C derived from rare and endangered plants.

If You Are Considering Taking a Dietary Supplement for Hepatitis C

  • Do not use any complementary health approach to replace conventional treatments for hepatitis C or as a reason to postpone seeing your health care provider about any medical problem.
  • Be aware that dietary supplements may have side effects or interact with conventional medical treatments. To learn more about using supplements, see the NCCAM fact sheet Using Dietary Supplements Wisely.
  • If you are pregnant or nursing a child, or if you are considering giving a child a dietary supplement, it is especially important to consult your (or your child’s) health care provider. Supplements can act like drugs, and many have not been tested in pregnant women, nursing mothers, or children.
  • Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care. For tips about talking with your health care providers about complementary health approaches, see NCCAM's Time to Talk campaign.

Key References

See All References

For More Information

NCCAM Clearinghouse

The NCCAM Clearinghouse provides information on NCCAM and complementary health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.

Toll-free in the U.S.: 1-888-644-6226

TTY (for deaf and hard-of-hearing callers): 1-866-464-3615

Web site: nccam.nih.gov

E-mail: info@nccam.nih.gov

National Digestive Diseases Information Clearinghouse

A service of the National Institute of Diabetes and Digestive and Kidney Diseases, the clearinghouse responds to inquiries, offers publications, and makes referrals. For a list of publications on hepatitis, go to digestive.niddk.nih.gov/ddiseases/pubs/hepatitis/.

Toll-free in the U.S.: 1-800-891-5389

Web site: www.digestive.niddk.nih.gov

National Institute of Allergy and Infectious Diseases (NIAID)

NIAID conducts and supports research to study the causes of allergic, immunologic, and infectious diseases, and to develop better means of preventing, diagnosing, and treating these illnesses.

Toll-free in the U.S.: 1-866-284-4107

Web site: www.niaid.nih.gov

Centers for Disease Control and Prevention (CDC)

The CDC is one of the major operating components of the U.S. Department of Health and Human Services. CDC collaborates to create the expertise, information, and tools that people and communities need to protect their health. For its National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, go to www.cdc.gov/nchhstp.

Web site: www.cdc.gov

NIH Clinical Research Trials and You

The National Institutes of Health (NIH) has created a Web site, NIH Clinical Research Trials and You, to help people learn about clinical trials, why they matter, and how to participate. The site includes questions and answers about clinical trials, guidance on how to find clinical trials through ClinicalTrials.gov and other resources, and stories about the personal experiences of clinical trial participants. Clinical trials are necessary to find better ways to prevent, diagnose, and treat diseases.

Web site: www.nih.gov/health/clinicaltrials/

PubMed®

A service of the National Library of Medicine (NLM), PubMed® contains publication information and (in most cases) brief summaries of articles from scientific and medical journals.

Web site: www.ncbi.nlm.nih.gov/pubmed

Acknowledgments

NCCAM thanks Leslie Curtis, M.A., and her colleagues at NIDDK, and Catherine Meyers, M.D., and John (Jack) Killen, Jr., M.D., NCCAM, for their contributions to the 2013 update of this publication.

This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCAM has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your primary health care provider. We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCAM.

* Note: PDF files require a viewer such as the free Adobe Reader.

NCCAM Pub No.: D422

Date Created: October 2008

Last Updated: May 2013

Source

June 13, 2013

Hepatitis C and Dietary Supplements: What the Science Says

May 2013

Milk Thistle

Milk thistle (scientific name Silybum marianum) is a plant from the aster family. Silymarin is an active component of milk thistle believed to be responsible for the herb’s health-related properties. Milk thistle has been used in Europe for treating liver disease and jaundice since the 16th century. In the United States, silymarin is the most popular dietary supplement taken by people with liver disease.

Strength of Evidence

  • Much research supports the conclusion that there little evidence of benefit for milk thistle as a treatment for hepatitis C.

Research Results

  • A 2012 controlled clinical trial, cofunded by NCCAM and NIDDK, showed that two higher-than-usual doses of silymarin were no better than placebo in reducing the high blood levels of an enzyme that indicates liver damage. In the study, 154 people who had not responded to standard antiviral treatment for chronic hepatitis C were randomly assigned to receive 420 mg of silymarin, 700 mg of silymarin, or placebo three times per day for 24 weeks. At the end of the treatment period, blood levels of the enzyme were similar in all three groups.
  • Results of the HALT-C study suggested that silymarin use by hepatitis C patients was associated with fewer and milder symptoms of liver disease and somewhat better quality of life, but there was no change in virus activity or liver inflammation. The researchers emphasized that this was a retrospective study (one that examined the medical and lifestyle histories of the participants). Its finding of improved quality of life in patients taking silymarin was not confirmed in the more rigorous 2012 study described above.
  • A 2009 Cochrane systematic review assessed the beneficial and harmful effects of milk thistle in patients with alcoholic liver disease and/or hepatitis B or C liver diseases and found that there is not enough high-quality evidence to support the use of this intervention.

Safety

  • Available evidence from clinical trials in people with liver diseases suggests that milk thistle is generally well-tolerated.
  • Side effects can include a laxative effect, nausea, diarrhea, abdominal bloating and pain, and occasional allergic reactions.
  • In NIH-funded studies of silymarin in people with hepatitis C that were completed in 2010 and 2012, the frequency of side effects was similar in people taking silymarin and those taking placebos. However, these studies were not large enough to prove that silymarin is safe for people with chronic hepatitis C.

Other Supplements

Other supplements have been studied for hepatitis C, but overall, no benefits have been clearly demonstrated.

Probiotics

Probiotics are live microorganisms that are intended to have a health benefit when consumed.

Strength of Evidence

  • Only a few studies have examined the effects of probiotics on hepatitis C.

Research Results

  • Research hasn’t produced any clear evidence that probiotics are helpful in people with hepatitis C.

Safety

  • Most people can use probiotics without experiencing any side effects—or with only mild gastrointestinal side effects such as intestinal gas —but there have been some case reports of serious adverse effects in people with underlying serious health conditions.
Zinc
Strength of Evidence
  • Preliminary studies, most of which were conducted outside the United States, have examined the use of zinc for hepatitis C.

Research Results

  • Zinc supplements might help to correct zinc deficiencies associated with hepatitis C or reduce some symptoms, but the evidence for these possible benefits is limited.
  • A few preliminary studies have looked at the effects of combining supplements such as lactoferrin, SAMe, or zinc with conventional drug therapy for hepatitis C. The evidence is not sufficient to draw clear conclusions about benefit or safety.

Safety

  • Zinc is generally considered to be safe when used appropriately, but it can be toxic if taken in excessive amounts.
Glycyrrhizin

Glycyrrhizin (or glycyrrhizic acid) is a compound found in licorice root.

Strength of Evidence

  • Glycyrrhizin has been tested in only a few clinical trials in patients with hepatitis C.

Research Results

  • There is currently not enough evidence to determine if glycyrrhizin is helpful for hepatitis C.

Safety

  • In large amounts, glycyrrhizin or licorice can be dangerous in people with a history of hypertension (high blood pressure), kidney failure, or cardiovascular diseases.
Colloidal Silver

Colloidal silver consists of tiny silver particles suspended in liquid. Colloidal silver products are often promoted for treating various diseases, including hepatitis C.

Strength of Evidence

  • Scientific evidence does not support the use of colloidal silver to treat any disease, and serious, irreversible side effects can result from its use.

Research Results

  • There is currently no research to support its use for hepatitis C.

Safety

  • Colloidal silver is known to cause serious side effects, including a permanent bluish discoloration of the skin called argyria.

NCCAM Clinical Digest is a service of the National Center for Complementary and Alternative Medicine, NIH, DHHS. NCCAM Clinical Digest, a monthly e-newsletter, offers evidence-based information on CAM, including scientific literature searches, summaries of NCCAM-funded research, fact sheets for patients, and more.

The National Center for Complementary and Alternative Medicine is dedicated to exploring complementary and alternative healing practices in the context of rigorous science, training CAM researchers, and disseminating authoritative information to the public and professionals. For additional information, call NCCAM’s Clearinghouse toll-free at 1-888-644-6226, or visit the NCCAM Web site at nccam.nih.gov. NCCAM is 1 of 27 institutes and centers at the National Institutes of Health, the Federal focal point for medical research in the United States.

Source

May 24, 2012

Herbal, Body Building, Diet Supplements Linked To Severe Liver Damage, Study

3978herbalrems

Even though supplements account for 18 percent of all liver injuries in the U.S. and their potential side effects and hepatotoxicity of supplements are still not well defined, nearly 4 out of 10 Americans take them. (David Gray/Reuters)

People taking body-building, weight-loss pills and other types of dietary and herbal supplements may be at risk for liver injury severe enough to warrant an organ transplant, experts warned.

By Christine Hsu | May 22, 2012

People taking body-building, weight-loss pills and other types of dietary and herbal supplements may be at risk for liver injury severe enough to warrant an organ transplant, experts warned at a press briefing at Digestive Disease Week in San Diego.

Even though supplements account for 18 percent of all liver injuries in the U.S. and their potential side effects and hepatotoxicity of supplements are still not well defined, nearly 4 out of 10 Americans take them.

"The number of cases in our network has increased over the years," Serrano said during the briefing. "There were no deaths, but 7% of patients needed a liver transplant. These are not trivial consequences," Dr. Jose Serrano of the National Institutes of Health said at the conference, according to Medpage Today.

According to the latest research from the U.S. Drug Induced Liver Injury Network, which evaluated patient information from eight locations across the U.S. from 2003 to 2011, dietary supplements used for body building and weight loss are the most common of any supplements to cause liver injury.

Serrano said that out of the 679 liver injury cases analyzed, 93 of the cases were caused by patients taking herbal or dietary supplements, adding that many of these patients were often younger than those who have similar liver injuries caused by other medications.

Among patients who had liver damage caused by supplements, 33 percent of them used them for body building, 26 percent for weight loss, and the remaining 31 percent used a variety of other supplements.

While the symptoms of liver injury caused by dietary or herbal supplements weren’t much different from injuries caused by other medications, researchers noted that one factor that distinguished liver injury from body building and supplements over drugs were itching, which occurred in more than 80 percent of the patients.

Around 66 percent of the patients in the study had to be hospitalized and 11 percent had developed abnormal liver function that lasted for more than 6 months.

While more than half of patients were only taking one type of supplement, 23 percent of patients used two or more supplements and 16 percent of patients look at least one supplement along with prescription drugs.

"There is so little regulation of the many products on the market," lead researcher Dr. Victor Navarro, professor at Thomas Jefferson University in Philadelphia, said in a meeting news release. "We couldn't possibly begin to figure out which products to target first without doing this research."

Dr. Donald Jensen of the University of Chicago warned that the biggest risk to patients that use supplements is not reporting it to a healthcare professional.

"Patients need to be label readers," Jensen told MedPage Today. "They can't just assume that everything out there is safe. There are things out there that can be potentially damaging."

He added that most patients may think that supplements "are food or that they're very safe. And there are some herbal medicines that probably are safe and may even do some benefit for people. I don't want to throw everything in the trash can. But, on the other hand, there are enough [supplements] that are damaging."

While not all people react negatively to supplements, Jensen said that there needs to be more research on potential patient interactions with herbal supplements.

"I don't think we're going to stop people from taking herbal medicines," he said. "I'd like to see the FDA regulate the toxic ones better, but otherwise I think the important next step is some scientific understanding of why some people get damaged and others don't."

Published by Medicaldaily.com

Source

Also See: Herbal, Dietary Supplements Take Toll on Liver

May 23, 2012

Herbal, Dietary Supplements Take Toll on Liver

    

By Cole Petrochko, Associate Staff Writer, MedPage Today

Published: May 22, 2012

Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and Dorothy Caputo, MA, BSN, RN, Nurse Planner

SAN DIEGO -- Patients taking herbal and dietary supplements may be at risk for liver injury severe enough to warrant an organ transplant, researchers said here.

In a review of national data, supplements accounted for 18% of liver injuries in the U.S., Jose Serrano, MD, of the National Institutes of Health, reported during a press briefing at Digestive Disease Week.

"The number of cases in our network has increased over the years," Serrano said during the briefing. "There were no deaths, but 7% of patients needed a liver transplant. These are not trivial consequences."

It's estimated that as much as 40% of the U.S. population uses herbal or dietary supplements, but their potential side effects, including hepatotoxicity, are not well defined.

The researchers looked at data from the Drug Induced Liver Injury Network, which evaluated patient information from eight sites across the U.S. from 2003 to 2011.

Of 679 cases of liver injury, 93 were attributed to herbal or dietary supplements, Serrano said, adding that these patients tended to be younger than those who have similar liver injuries due to other medications. The majority of these patients were white.

Among patients that had used supplements, 33% used them for body building, 26% for weight loss, and the remaining 31% used a variety of other types of supplements.

Serrano said the symptoms of liver injury caused by supplements weren't different from those caused by other medications. But one factor that distinguished liver injury from body building supplements over the others was itching, which occurred in 86% of patients.

Those who had liver injury resulting from either body building or weight-loss supplements also tended to have a longer latency time between exposure and injury compared with liver injury from other medications or the miscellaneous category of dietary supplements.

Weight-loss products also appeared to be associated with a more hepatocellular pattern of injury, while body building supplements (usually anabolic steroids) had a more mixed pattern with increments on total bilirubin, Serrano said.

Most of the patients (66%) had to be hospitalized, and 11% developed alterations in liver function that persisted for at least 6 months, he added. The median serum alanine-aminotransferase (ALT) at presentation was 533 U/L, the alkaline phophatase was 166 U/L, and the total bilirubin was 7 mg/dL.

The R-value, which represents liver injury pattern, was in the hepatocellular range (>5%) in 65% of the patients with a median ALT of 1,275 U/L. The range for normal ALT is generally between 7 and 56 units U/L.

Symptoms included:

  • Jaundice (78% of patients)
  • Nausea (60%)
  • Itching (58%)
  • Abdominal pain (47%)

The majority of patients (60%) used only one type of supplement, while 23% used two or more supplements, and 16% used at least one supplement concurrently with prescription drugs.

While the most common injury pattern seen was hepatocellular, the distribution of overall causality scores was not significantly different across injury patterns (P=0.30), the authors stated.

The biggest risk to patients that use supplements is not reporting supplement use to a healthcare professional, noted Donald Jensen, MD, of the University of Chicago and DDW press conference moderator.

"Patients need to be label readers," Jensen told MedPage Today. "They can't just assume that everything out there is safe. There are things out there that can be potentially damaging."

He added that patients think supplements "are food or that they're very safe. And there are some herbal medicines that probably are safe and may even do some benefit for people. I don't want to throw everything in the trash can. But, on the other hand, there are enough [supplements] that are damaging."

He said that future research on supplements should focus on potential patient interactions with herbal supplements, noting that not all patients have negative interactions with them.

"I don't think we're going to stop people from taking herbal medicines," he said. "I'd like to see the FDA regulate the toxic ones better, but otherwise I think the important next step is some scientific understanding of why some people get damaged and others don't."

Navarro disclosed consultancy work for Merck.

Co-authors disclosed relationships with Boehringer-Ingelheim, Clinuvel, Novartis, American Porphyria Foundation, Iron Disorder Institute, Vertex, Lundbeck, Bristol-Meyers Squibb, GlaxoSmithKline, Siemens Medical Solutions, Roche, Gilead Sciences, Tibotec, and Catalent.

Primary source: Digestive Disease Week
Source reference:
Navarro VJ, et al "Herbal and dietary supplement induced hepatotoxicity in the U.S." DDW 2012; Abstract 167.

Source

January 27, 2012

FDA Supplement Guidance Not Strict Enough, MD Says

By Emily P. Walker, Washington Correspondent, MedPage Today
Published: January 26, 2012

An FDA proposal to require dietary supplement manufacturers to submit data proving their product is safe doesn't go far enough, according to a physician writing in the New England Journal of Medicine.

More than 100 million Americans spend more than $28 billion on vitamins, minerals, herbal ingredients, amino acids and other natural products in the form of dietary supplements each year, "assuming they are both safe and effective," wrote Pieter A. Cohen, MD, of Harvard Medical School and the Cambridge Health Alliance.

But they have no assurance that the products are safe because FDA regulation of supplements is too weak, Cohen wrote in a Perspective piece.

By law, ingredients that were used and sold in supplements prior to 1994 can be marketed without any proof that they are safe or effective. But under a law called the Dietary Supplement Health and Education Act (DSHEA), manufacturers of any ingredient introduced after 1994 must provide the FDA with evidence supporting "a reasonable expectation of safety."

Cohen said that part of the law "has thus far not been enforced."

Since DSHEA became law more than 15 years ago, the number of supplements on the market has gone from 4,000 to more than 55,000. Since 1994, the FDA has received proper notification for 170 new supplement ingredients, "undoubtedly a small fraction of the ingredients for which safety data should have been submitted," Cohen said.

The FDA has mounted a new effort to discourage the sale and use of nutritional supplements that contain ingredients that are regulated as drugs. Last year, the agency issued draft guidance meant to inform supplement manufacturers about what information they must submit to the FDA, including spelling out when an ingredient is considered old and when it's considered new. (A synthetically produced replica of a botanical product, for instance, would be considered new).

In addition, the FDA is proposing that the guidance call for in vitro, animal, and long-term tolerability testing for supplements that would be marketed at higher doses than those historically ingested.

"The FDA's guidance provides a thoughtful framework for evaluating the safety of new ingredients and if implemented it would lead to substantial improvement in safety," Cohen wrote, but he said he didn't think the FDA goes far enough.

He said under the guidance, companies can use historical data (instead of clinical trials) to prove that a supplement is safe, and Cohen said that the FDA can't assess the safety of new products scientifically without experimental data.

Cohen also said that under the guidance, manufacturers would not be required to submit both favorable and unfavorable data to the FDA, so they could cherry-pick only positive data to submit.

The dietary supplement industry largely opposes the draft regulation.

One opponent is the Natural Products Association, whose 1,900 members include small health food stores and large supplement manufacturers. The group submitted its official response to the FDA's proposal in November and said the agency is "overstepping" and that the rules would have a "chilling effect" on the dietary supplement industry.

"The draft guidance as currently written sets up inappropriate barriers to market entry, imposes food additive criteria, and requires multiple ... notifications beyond those required by law," the group wrote.

Cohen said it's true that the proposed requirements would impose similar standards on supplements and food additives.

"Industry advocates are correct insofar as DSHEA does not hold established (pre-1994) supplement ingredients to the same safety standards as food additives: a chemical preservative sprayed inside a can of tomato soup or the purple dye in Jell-O requires much more evidence of safety than ingredients used in supplements," Cohen wrote.

Cohen urged the FDA to not change its proposal because of protests from industry.

"If the FDA succumbs to industry pressure, the public health consequences will be significant, as hundreds of thousands of Americans continue to turn to new supplements to sustain their health and treat their ailments," he said.

The FDA is accepting comments on the draft guidance until Feb. 1.

Cohen reported no financial conflicts of interest, other than having his travel paid for to be a guest on an episode of the Dr. Oz Show that dealt with supplements.

Source

Also See: Dietary supplements' safety regulation: too much or not enough?

January 26, 2012

Dietary supplements' safety regulation: too much or not enough?

By Melissa Healy, Los Angeles Times/For the Booster Shots blog

January 26, 2012, 5:03 p.m.

A new proposal to toughen the Food and Drug Administration's power to regulate dietary supplements has the makers of vitamins, minerals and botanical extracts up in arms. But an editorial in the New England Journal of Medicine says the drug-safety agency's proposed new powers do not go nearly far enough.

To expand its current $28-billion-a-year market, the dietary supplements industry is widely devising and selling formulations that use "novel" products -- minerals, plants, or amino acids that appear newly promising, which have not circulated widely in the United States before, or which are offered in "mega-doses" much higher than have been customarily used in supplements. An industry that produced and marketed 4,000 distinct products in 1994, when the regulatory framework for dietary supplements was written into law, now markets about 55,000 products to Americans who believe them to be safe to take.

Since 1994, those selling "novel" products have been required to provide federal regulators with evidence supporting a product's "reasonable expectation of safety." In a New England Journal of Medicine "Perspective" article published this week, Dr. Pieter Cohen, assistant professor of Medicine at Harvard University, suggests that even that vague standard has gone unenforced by the FDA and likely ignored by manufacturers eager to bring their supplements to market.

But in an effort to keep up, the FDA last July laid out a new raft of rules for those marketing "novel" dietary supplements in the United States. The new rules aim to spell out how a "reasonable expectation of safety" should be established. In some cases, the agency would accept documentation of a supplement's "historical use" outside the United States. For "mega-doses" that exceed commonly used levels of a given supplement, the agency wants to see evidence of safety from animal studies and from test-tube studies. (While trials using human subjects in testing a supplement's long-term use are allowed, they're not required).

These new requirements, writes Dr. Cohen, aren't enough. The "historical use" of a product where no one is looking for possible ill effects is a standard too low to assure safety, he writes. He adds that supplement manufacturers are under no obligation to share unfavorable safety data on a product with the FDA, so long as they offer studies that show the product is safe. And for products with no history of common use -- or marketed at super-high doses, "not even single-dose tolerability studies in humans would be required" by the new rules.

"If the FDA succumbs to industry pressure, the public health consequences will be significant," writes Cohen.

Source

January 18, 2011

Review of liver injury associated with dietary supplements

Liver International
Early View (Articles online in advance of print)

Felix Stickel 1, Kerstin Kessebohm 2, Rosemarie Weimann 3, Helmut K. Seitz 4

Article first published online: 11 JAN 2011
DOI: 10.1111/j.1478-3231.2010.02439.x
© 2011 John Wiley & Sons A/S

Author Information
1 Department of Visceral Surgery and Medicine, Institute of Clinical Pharmacology and Visceral Research, Inselspital, University of Berne, Berne, Switzerland
2 Institute of Clinical Pharmacology and Visceral Research, University of Berne, Berne, Switzerland
3 Institute of Pathology, University of Berne, Berne, Switzerland
4 Department of Medicine, Center of Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, University of Heidelberg, Heidelberg, Germany
* Correspondence: Correspondence Felix Stickel, MD, Department of Visceral Surgery and Medicine, Institute of Clinical Pharmacology and Visceral Research, Inselspital, University of Bern, Murtenstr. 35, 3010 Bern, Switzerland Tel: +41 31 632 87 28 Fax: +41 31 632 49 97 e-mail: felix.stickel@ikp.unibe.ch

Keywords:
anabolic steroids; Camellia sinensis; cholestasis; hepatitis; retinoid toxicity; toxic liver injury

Abstract

Dietary supplements (DS) are easily available and increasingly used, and adverse hepatic reactions have been reported following their intake. To critically review the literature on liver injury because of DSs, delineating patterns and mechanisms of injury and to increase the awareness towards this cause of acute and chronic liver damage. Studies and case reports on liver injury specifically because of DSs published between 1990 and 2010 were searched in the PubMed and EMBASE data bases using the terms ‘dietary/nutritional supplements’, ‘adverse hepatic reactions’, ‘liver injury’; ‘hepatitis’, ‘liver failure’, ‘vitamin A’ and ‘retinoids’, and reviewed for yet unidentified publications. Significant liver injury was reported after intake of Herbalife® and Hydroxycut products, tea extracts from Camellia sinensis, products containing usnic acid and high contents of vitamin A, anabolic steroids and others. No uniform pattern of hepatotoxicity has been identified and severity may range from asymptomatic elevations of serum liver enzymes to hepatic failure and death. Exact estimates on how frequent adverse hepatic reactions occur as a result of DSs cannot be provided. Liver injury from DSs mimicking other liver diseases is increasingly recognized. Measures to reduce risk include tighter regulation of their production and distribution and increased awareness of users and professionals of the potential risks.

Abbreviations
ALF, acute liver failure; DILI, drug-induced liver injury; DS, dietary supplements; FDA, Food and Drug Administration; HSC/MFB, hepatic stellate cells/portal myofibroblasts

The use of dietary supplements (DS) containing vitamins, anti-oxidants, fibre, trace elements, proteins, amino acids and herbal constituents has become a major health trend in affluent societies (1, 2). Consumption of DS in the USA has doubled to 18.9% of adults admitting their use only between 1999 and 2004 (3, 4); some investigations report their consumption up to 47% in certain subgroups such as among elder, non-smoking females with higher education (5). The rising popularity of DS is probably because of an increased awareness of consumers towards health in general and the desire to prevent diseases by an optimized nutritional status, and the persuasion that these treatments are safe (1, 2, 5, 6). Further, DS do not require prescriptions from health professionals allowing largely unrestricted access to relatively cheap products. Consequently, marketing such products has become a multibillion business largely unregulated by official health authorities (6–8).

In the USA, DS are expected to meet the standards outlined in the Dietary Supplement and Health Education Act published in 1994, which allows distribution without prior approval of their efficacy and safety by the Food and Drug Administration (FDA) (9). This simplified licensing practice does not ensure efficacy and safety in the same strict way as with the approval of conventional medications and treatments. Similarly, the European Union has set forth legislative measures for the distribution and marketing of DS and functional foods that are outlined in the European Commission 2000 White Paper on Food Safety (10, 11). This set of legislation pays tribute to the fact that DS may harbour specific problems because of their complex composition, particularly with respect to quality aspects, and defines guidelines for conducting premarketing in vitro and in vivo studies.

While adverse hepatic reactions from xenobiotics are well documented by pre- and post-marketing pharmacovigilance, the situation for DS is less well depicted as widespread and uncontrolled use and under-reporting prevent the determination of their true incidence. Additionally, a low awareness of users and providers towards their potential harms impedes their recognition as the causative agent in incidents of hepatotoxicity. Consequently, estimates of the frequency of DS-associated hepatic injury are likely imprecise and, possibly, too low. The proportion of hepatotoxicity ascribed to DS varies from 2% in a Spanish study (12) describing 531 cases of drug-induced liver injury (DILI) to approximately 10% in a series from the US Drug-Induced Liver Injury Network (DILIN) (13). Figures were as high as 35% in a small series of 20 patients developing acute liver failure with DS exposure as the only identifiable cause of liver damage (14).

Our article aimed to review and describe the literature on liver injury because of DS, delineate patterns and mechanisms of injury and to increase the awareness towards this possible cause of acute and chronic liver damage.

Literature search methodology

In February 2010, case reports and series thereof on liver injury specifically occurring following the consumption of DS published between 1990 and 2010 were searched in PubMed and EMBASE data bases using the terms ‘adverse hepatic reactions’, ‘anabolic steroids’, ‘Camellia sinensis’, ‘dietary/nutritional supplements’, ‘Herbalife’, ‘hepatitis’, ‘Hydroxycut’, ‘green tea’, ‘liver failure’, ‘liver injury’, ‘Noni’, ‘retinoids’, ‘vitamin A’ and critically reviewed. Retrieved publications were searched for yet unidentified publications. Remedies were considered DS if consumed as an aid to improve nutritional status, to loose weight or to treat constipation. Cases of liver injury from preparations taken for other causes than nutritional purposes were not included. No language restriction was used.

While hepatotoxicity from herbal medicines in general has been addressed in several reviews (15–18), summaries specifically devoted to liver-related risks along with DS are scarce (19). In the following, a panel of rather distinct DS preparations associated with liver injury are described (Table 1).

Specific dietary supplements associated with liver injury

Herbalife® (Los Angeles, CA, USA) sells nutritional and herbal supplements as tablets, capsules, drinks and energy bars for weight control, improvement of nutrition, ‘well-being’ and cosmetics. In 2006, the stock market quoted that Herbalife® company had a revenue of US$3.1 billion via online marketing or through independently operating sales agents.

There are so far six published reports on liver damage following the intake of Herbalife® products since 2007 describing 34 cases from five countries (Switzerland, Israel, Spain, Argentina and Iceland), although Herbalife® products are sold in at least 60 countries worldwide (20–25). Individual data of all reports are displayed in Table 2. Pattern of injury was mostly hepatocellular, but mixed and cholestatic enzyme patterns were also observed. Severity ranged from mild to severe hepatic damage including cirrhosis and acute liver failure requiring liver transplantation, which was successful in one patient while the second died because of post-operative complications. Causality between intake of Herbalife® products and the evolution of liver injury was assessed by widely used scores (26, 27) in five of the six reports and considered ‘certain’ in at least five patients by a positive rechallenge reaction and ‘probable’ in the majority of the remaining cases (20, 21).

Figure 1. Liver histology from a patient with secondary biliary cirrhosis following long-term intake of numerous Herbalife® nutritional supplements contaminated with Bacillus subtilis. (A) Enlargement of portal tracts with fibrosis, chronic inflammation and porto-lobular interface activity as well as ductular proliferation of the bile ducts with reactive changes of the epithelium (HE staining). (B) Immunohistochemistry with anticytokeratin 7 indicating bile duct such as loss of biliary lumina and significant lympho-epithelial infiltration (see arrow).

Camellia sinensis (green tea)
 
Green tea is among the most frequently consumed drinks in the USA and often used as a DS. The first report on liver injury following the ingestion of green tea extracts and preparations thereof was published in 1999 (31), and since then, numerous consecutive cases were reported to regulatory agencies worldwide. With effect of April 2003, the manufacturer of Exolise® (Arkopharma, Carros, France), a hydro-alcoholic extract of C. sinensis, has revocated all of their products after altogether 13 cases of acute liver damage following its intake were reported to the French pharmacovigilance authorities (Agence Francaise de Securité Sanitaire de Produits de Sanité; http://www.afssaps.sante.fr/). As a reaction to these accumulating reports, the US Pharmacopeia performed a systematic review of all cases accessible from PubMed, EMBASE and pharmacovigilance data bases in the USA, Canada, UK and Australia reporting on 34 single cases of liver injury following the ingestion of numerous different green tea preparations (32). Herein, case reports were retrospectively evaluated according to the Naranjo causality algorithm scale (33), and 27 reports pertaining to liver damage were labelled as ‘possibly’ and the remaining seven cases as ‘probably’ linked to green tea. Another Medline search review of cases on green tea liver injury from the same year also retrieved 34 published reports and described two further yet unpublished cases (34). On histological examination, livers of patients revealed inflammatory reactions, cholestasis, occasionally steatosis and necrosis. Although there was some overlap of single reports between these two review articles, collected case reports were not identical and jointly provided details on 58 cases of hepatotoxicity along with the intake of green tea extracts, powdered leaves, green tea infusions and hydro-alcoholic and aqueous extracts. In Mazzanti's summary, no causality re-evaluation was performed, but information on de- and rechallenge is provided for every case indicating a positive rechallenge response with accelerated recurrence of liver injury in seven of 36 incidents, which strongly suggests a causal relationship between the observed liver injury and green tea consumption. Of concern is that there was one reported death. However, a note of caution is warranted in many of the cases regarding an exclusive assignment of causality to green tea, because many patients who experienced adverse hepatic reactions also took numerous other products with a published record of hepatotoxicity, such as Cassia angustifolia, Hydroxycut and Ephedra sinica (for all three, please see below). Since these two review articles, additional cases have been published from Belgium reporting on a 42-year-old female patient who developed cholestatic hepatitis 6 months after starting Densitive® (Kerastase Nutritients, L'Oréal, Paris), which contains C. sinensis (35). Upon dechallenge, a full recovery was recorded. Other causes of liver injury were carefully excluded, but formal causality assessment using an established score was not performed. In the second case, jaundice, weight loss and subacute hepatitis developed in a 76-year-old man who regularly drank green tea infusions (36). Histology showed marked necro-inflammation, and transiently elevated antismooth muscle auto-antibodies were suggestive of autoimmunity induced by green tea constituents.

The mode of toxicity derived from green tea still remains incompletely understood but could be because of (−)-epigallocatechin gallate or its metabolite (−)-epicatechin gallate, which, under certain conditions such as fasting, can induce oxidative stress-related liver damage (37). Interestingly, in vitro and in vivo experimental studies have demonstrated both hepatoprotective as well as hepatotoxic properties (37–40). Along this line, support for potentially hepatoprotective activity from green tea extracts comes from clinical studies studying its therapeutic effects in humans with liver diseases including liver cancer, cirrhosis and steatosis. Four randomized-controlled clinical trials, two cohort, one case–control and three cross-sectional studies from China, Japan and the USA were recently subjected to a systematic review and found overall favourable effects from green tea as reflected by reduced mortality, attenuated steatosis and reduced incidence of primary liver cancer (41).

Whether the risks from green tea consumption outweigh their benefits remains open, but current evidence as outlined above suggests a causal relationship between intake of green tea-containing products and hepatotoxicity. Consequently, in their systematic review, the US Pharmacopeia included a cautionary statement on green tea indicating this possibility (32).

Usnic acid

Some years ago, several cases of acute liver failure requiring liver transplantation following the intake of LipoKinetix®, a product extracted from lichens and fungi and sold as DS capsules, were reported (42–45). Onset of liver injury was usually acute with a maximum latency of 3 months and the injury pattern hepatocellular with massive elevations of ALT and AST. Lipokinetix contained usnic acid and was marketed as a weight-loss remedy. Efficacy for this indication was postulated based on its function as an uncoupler of the respiratory chain, which in principle can augment weight loss (46). Apart from usnic acid, LipoKinetix® contained norephedrine hydrochloride, diiodothyronine, yohimbine hydrochloride and caffeine, which were confirmed by analysing the used LipoKinetix® lots. None of the ingredients were associated previously with liver damage and inadvertent contamination was excluded. These serious events caused the withdrawal of LipoKinetix® from the market.

Hydroxycut

Only recently, several Hydroxycut products were retracted by the manufacturer following a warning posted by the FDA in May 2009 because of 23 reports of liver injury including cases with acute hepatic failure and subsequent liver transplantation (47–49). Hydroxycut preparations were sold as powder, capsules and tablets by conventional retailers, through Internet sources and via direct television marketing. Hydroxycut was used to support weight loss and by body builders. The manufacturer had been charged previously with several lawsuits for unfounded health claims. Before May 2009, its primary ingredients included Garcinia cambogia, Gymnema sylvestre, chromium polynicotinate, caffeine and green tea. Published cases were recently reviewed and showed acute onset after several weeks of intake with high levels of serum aminotransferases in the majority of cases, while others presented with a more insidious, usually cholestatic course (50).

Miscellaneous

Various other DS have been associated with acute and subacute liver damage such as Senna (C. angustifolia), which is used as a powder, tea or suppository to treat constipation. According to our search, a total of five reports with altogether five individual cases describe the evolution of variable liver pathologies including acute cytolytic hepatitis, subacute cholestatic hepatitis, acute liver failure and portal vein thrombosis upon consumption of Senna products (51–55). In some reports, Senna preparations were self-made or ingested excessively such as in a young woman taking approximately 10 times the recommended dose who developed cytolytic hepatitis, which completely subsided after stopping Senna (51). The causal relationship between the preparation and hepatitis was confirmed through a positive rechallenge in two cases (51, 52). Senna is biotransformed via intestinal bacteria to rhein anthrone, which is highly reactive and requires binding to glucuronide and sulphate via phase I oxidation for renal excretion (56). Rhein anthrone is suspected to function as an uncoupler of the respiratory chain, and can therefore possibly affect hepatocyte integrity under certain circumstances, such as in genetically predisposed individuals. Seybold et al. (52) describe a case of increased toxicity of Senna tea in a homozygous carrier of a genetic cytochrome P450 2D6 variant rendering the individual a poor metabolizer for phase I hepatic detoxification reactions.

Noni juice (Morinda citrifolia) has become increasingly popular in Western countries as a health tonic. Consumption of Noni was the presumed cause of acute hepatitis in a 45-year-old man who drank a glass of this tropical fruit over several weeks for preventive reasons and for ‘strengthening the immune system’ (57). Other possible aetiologies of acute hepatitis were ruled out and liver tests rapidly turned normal after the cessation of Noni intake. Since this first report in 2005, five additional cases have been published from Austria, Germany and Spain (58–61). Remarkably, two patients experienced liver failure of which one required liver transplantation. The pattern of liver injury was hepatocellular in all cases and occurred rapidly within a few weeks of exposure. Causality was formally assessed in two publications, but not considered ‘certain’ in any of the cases because no rechallenge was used. Also, at least two of totally six patients had concomitant medication with known hepatotoxic potential, such as interferon-β (62) and a Chinese herbal mixture (63) respectively. Responsibility of Noni preparations as the cause of liver injury in these cases is challenged by one of the manufacturers of Noni products (64, 65) by demonstrating experimental evidence of no dose-dependent hepatotoxicity and even hepatoprotective properties in some animal models of chronic liver injury (66, 67). However, a lack of dose-dependent hepatotoxicity does not exclude idiosyncratic drug toxicity, e.g. by inducing autoimmune reaction as shown by Yuce et al. (59) who found excessively high liver–kidney microsomal antibodies of 1:3840 in a patient drinking Noni juice for 4 weeks. Nevertheless, the true underlying pathophysiology of Noni-associated liver injury remains elusive because active components within Noni extracts such as flavonoids, glycosides, vitamins, anthraquinones and polyunsaturated fatty acids are not known to be hepatotoxic.

Chinese herbs have become highly popular among consumers in Western countries because of a prevailing belief in their efficacy and safety. Among many others, Ma huang (E. sinica) is marketed in the USA as a nasal decongestant and bronchodilator, and more recently as a weight-loss remedy. The first report of Ma huang-associated liver injury was about a woman developing acute hepatitis together with elevated antinuclear antibodies (ANA) and smooth muscle antibodies (SMA) after only 3 weeks of intake of Ma huang, but liver abnormalities resolved after its discontinuation (68). Another report suggested that intake of Ma huang was the cause of acute liver failure in a 58-year-old patient initiating her listing for high-urgency liver transplantation who also presented with elevated titres of SMA (69). Another report suggested an association of Ma huang-related liver injury with compound heterozygosity for the C282Y and H63D mutation in the haemochromatosis gene, proposing that excess hepatic iron could aggravate hepatotoxicity, possibly via enhancing oxidative stress (70). The largest series on severe liver injury because of the intake of Ma huang by Neff et al. (71) describes 10 cases of acute cytolytic hepatitis of which two subjects required liver transplantation and one died, while the remaining seven patients recovered spontaneously. These cases of severe liver damage and others referring to cardiac toxicity have prompted a warning by the FDA for the use of Epedra-containing DS such as Ma huang (72).

In 1986, Germander (Teucrium chamaedrys) was approved as a drug for the supportive treatment of obesity in France. Its subsequent widespread use precipitated numerous reports on acute, chronic and even fulminant hepatitis to the French pharmacovigilance authorities in 1992 (73–75). Within a median of 2 months, intake of daily doses between 600 and 1600 mg/day precipitated acute cytolytic hepatitis or chronic hepatitis with fibrosis and even cirrhosis (74, 76). All patients recovered after the discontinuation of treatment, but some relapsed under re-exposure. Germander contains saponins, glycosides, flavonoids and neoclerodane diterpenoids, which were shown to be converted into diterpenoid toxic metabolites by cytochrome P450 3A in mice (77). In conditions of glutathione depletion – such as during fasting – or after induction of cytochrome P450 3A, toxic diterpenoids are potent inducers of hepatocyte apoptosis (78, 79). Hence, in 1992, the license for Germander-containing products was withdrawn.

‘Onshidou-Genbi-Kounou’, another herbal marketed for weight loss, seemed the likely cause of chronic hepatitis in a 52-year-old Japanese woman who took this preparation for 2 months (80). Serum levels of liver enzymes were elevated to >1500 IU/l and ANA were positive with 1:160. All other possible causes for chronic hepatitis were excluded, and liver histology was compatible with drug-induced autoimmune hepatitis. The patient recovered completely without intervention on cessation of ‘Onshidou-Genbi-Kounou’ intake. In a larger series from Japan describing 12 patients with acute hepatitis after taking ‘Onshidou-Genbi-Kounou’ and ‘Chaso’ for weight loss, two patients developed liver failure of which one survived after successful liver transplantation and the other one died (81). ‘Onshidou-Genbi-Kounou’ contains several natural compounds (amachazuru, tea leaf, barbaloin, total saponin and polyphenols) and N-nitroso-fenfluramine. The latter demonstrated induction of mitochondrial permeability transition and hepatocyte apoptosis following uncoupling of oxidative phosphorylation and intracellular ATP depletion (82, 83).

Vitamin A-associated liver injury

DS fortified with vitamin A are used to prevent night blindness, to increase immune function and to promote health in general. Liver injury related to hypervitaminosis A is well known for many decades and comprises mild elevations of serum liver enzymes, cholestatic hepatitis, non-cirrhotic portal hypertension, progressive fibrosis and cirrhosis (84–87). Toxicity does not usually occur with standard doses below 50 000 IU/day as contained in common multivitamin preparations, but individual tolerability may vary (88). Pre-existing liver lesions including steatosis, chronic alcohol consumption, comedication with other potentially hepatotoxic drugs and young age may predispose certain individuals to develop vitamin A hepatotoxicity (89, 90). Several case reports have demonstrated significant hepatotoxicity with vitamin A doses as low as 20 000 IU/day (91), and upper limits of tolerability may even be lower in regular alcohol consumers (92).

Toxicity is mediated to the dose-dependent effect of retinoids on hepatic stellate cells/portal myofibroblasts (HSC/MFB), which are the key effector cells in the evolution of fibrosis and cirrhosis (93). Upon excessive vitamin A exposure, HSC/MFB start to produce collagens, downregulate collagenase activity and acquire the ability of contraction leading to elevation of blood pressure in the portal vein. In addition to this direct impact on HSC/MFB function and activity, retinoids can be transformed into metabolites that affect mitochondrial function and hepatocyte viability with resulting liver cell apoptosis (94, 95). This was shown to occur particularly when co-administered with alcohol. Dan and colleagues showed that retinoids can be transformed via alcohol-induced cytochrome P450 2E1 into highly reactive and toxic polar metabolites, which cause hepatocyte apoptosis upon caspase 3 activation (Fig. 2). Hence, health professionals should consult users carefully about the potential dangers of vitamin A, particularly when intended for longer period, in children and regular alcohol consumers.

Figure 2. Retinoids are substrates of cytochrome P450 2E1 and may be transformed into toxic polar retinoid metabolites. These can damage mitochondria by disrupting the mitochondrial membrane potential, releasing pro-apoptotic factors (e.g. cytochrome C) and initiating caspase activation and hepatocellular apoptosis.

Anabolic steroids

Anabolic steroids are an integral part of the nutritional concept of many athletes to improve fitness, muscle gain and exercise performance. Their use is widespread although anabolics are classified as class III substances and therefore subdued to strict rules (96). However, access via inofficial and sometimes illegal sources is easy, and therefore, in spite of tight rules, further adverse hepatic reactions following the consumption of anabolic steroids can be expected. Hepatotoxicity has been frequently described and patterns of injury delineated. Liver lesions include intrahepatic cholestasis, hepatitis, adenoma and hepatocellular carcinoma and rare malformations such as peliosis hepatis, a rare pathological entity characterized by the gross appearance of multiple cyst-like, blood-filled cavities within the liver (97, 98). A recent case series demonstrated the evolution of cholestasis 2 weeks after the intake of anabolic steroids had been stopped. All patients recovered fully after intake had been terminated (99). Even more worrisome is the observation that some DS may contain anabolic steroids sufficient to precipitate liver injury, as demonstrated by a recent case report showing cholestasis in two young men who took DS to enhance their body-building performance (100). Another case presented with a less favourable course as prolonged intrahepatic cholestasis and subsequent kidney failure developed (101). The precise mechanism underlying toxicity is yet unclear, but experimental data indicate direct hepatocellular toxicity from steroids via increased oxidative stress and subsequent impairment of function of the canalicular bile salt export pump (100).

A recent case–control study from Brazil suggested that anabolic steroids could be a cause of toxicant-associated non-alcoholic fatty liver disease (TAFLD) by comparing 95 recreational body builders using anabolic steroids with 85 non-users. In those consuming anabolic steroids, 12.6% of subjects revealed criteria compatible with TAFLD such as steatosis on ultrasound imaging, elevated serum transaminases and exclusion of relevant alcohol intake or concomitant medication, but no overweight or insulin resistance suggestive of metabolic NAFLD. In turn, 2.4% of body builders not using anabolic steroids showed clinical signs and findings suggestive of NAFLD. The authors concluded that the intake of anabolic steroids could be a cause of non-metabolic, but toxicant-associated NAFLD (102).

Conclusion

Hepatic injury secondary to consumption of DS is recognized, although its exact frequency remains unclear, mostly because evidence relies exclusively on case reports. Lack of stringent diagnostic criteria, poor awareness of consumers and prescribers, easy and uncontrolled access and under-reporting account for this epidemiological gap of knowledge. Diagnostic assessment of DS-associated should be made more consistent, and customized specifically to DS. Although causality categories reached in many of the published reports suggest a causal relationship between liver injury and the intake of certain DS products, pitfalls exist related to the used diagnostic scales, which have all been criticized for variable reasons and of which none is unequivocally accepted as being suitable for the evaluation of DS as a cause of liver injury. While the WHO score is not specifically designed to evaluate DILI (103), the Naranjo adverse drug reaction probability scale (33) was recently found to have low sensitivity (54%), poor negative predictive value (29%) and to lack reproducibility in a large series of cases of suspected hepatotoxicity (104) when compared with the Roussel Uclaf Causality Assessment Method (RUCAM) (26, 105). A clinical diagnostic scale has been suggested as a simple tool to assess adverse hepatic drug reactions and showed good correlation with RUCAM in one study (106), but not in another (107). To conclude, all used scores reveal merits and limitations, but a common consensus on which one is the best to apply in causality assessment of DS-associated liver damage has never been reached. In an approach to compensate for this lack of common agreement, recently, the DILIN was established to advance our understanding and research into DILI by initiating a prospective registry of patients with DILI for future studies into host clinical, genetic, environmental and immunological risk factors, and to develop standardized nomenclature, terminology and causality assessment instruments (108). Patients with liver injury because of herbal products are also eligible to be included. Herein, a causality score ranging from 1 (definite) to 5 (unlikely) as well as a severity score ranging from 1 (mild) to 5 (fatal) is applied by three hepatologists of the DILIN study group, thereby minimizing individual biases. In addition to accounting for the input of the reporting investigator who took the history, performed the physical examination and supervised the data collection, a prospective evaluation of other potential causes of liver injury and serial laboratory data through at least 6 months of follow-up are offered. However, the DILIN expert opinion is limited by its lack of generalizability and a low level of agreement between the three hepatologists (109). Hence, a certain degree of inaccuracy in assigning causality remains until better diagnostic measures are established.

Apart from diagnostic measures, better regulatory measures to assure safety and timely recognition of potentially harmful products require improvement and, thus, efforts of pharmacovigilance authorities and healthcare providers must jointly act to minimize risks and protect consumers. Manufactures must spend utmost care in providing users with clean and unadulterated products and should be held liable if this accidentally or carelessly fails. Finally, consumers should develop a more critical attitude towards the expectations and hopes associated with DS use in largely healthy individuals, and turn to measures for which safety data are known, and efficacy is proven.

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