Herbal toxicity and fatal hepatic failure

Herb-induced liver injury: Systematic review and meta-analysis

BACKGROUND

The use of herbal supplements and alternative medicines has been increasing in the last decades. Despite popular belief that the consumption of natural products is harmless, herbs might cause injury to various organs, particularly to the liver, which is responsible for their metabolism in the form of herb-induced liver injury (HILI).

AIM

To identify herbal products associated with HILI and describe the type of lesion associated with each product.

METHODS

Studies were retrieved using Medical Subject Headings Descriptors combined with Boolean operators. Searches were run on the electronic databases Scopus, Web of Science, MEDLINE, BIREME, LILACS, Cochrane Library for Systematic Reviews, SciELO, Embase, and Opengray.eu. Languages were restricted to English, Spanish, and Portuguese. There was no date of publication restrictions. The reference lists of the studies retrieved were searched manually. To access causality, the Maria and Victorino System of Causality Assessment in Drug Induced Liver Injury was used. Simple descriptive analysis were used to summarize the results.

RESULTS

The search strategy retrieved 5918 references. In the final analysis, 446 references were included, with a total of 936 cases reported. We found 79 types of herbs or herbal compounds related to HILI. He-Shou-Wu, Green tea extract, Herbalife, kava kava, Greater celandine, multiple herbs, germander, hydroxycut, skullcap, kratom, Gynura segetum, garcinia cambogia, ma huang, chaparral, senna, and aloe vera were the most common supplements with HILI reported. Most of these patients had complete clinical recovery (82.8%). However, liver transplantation was necessary for 6.6% of these cases. Also, chronic liver disease and death were observed in 1.5% and 10.4% of the cases, respectively.

CONCLUSION

HILI is normally associated with a good prognosis, once the implied product is withdrawn. Nevertheless, it is paramount to raise awareness in the medical and non-medical community of the risks of the indiscriminate use of herbal products.

Herbal Product Contamination and Toxicity

Herbal poisoning exposures reported to poison centers increased by 344% after passage of the Dietary Supplement Health and Education Act, with 24412 exposures reported in 2003. Increased toxicity is speculated to be related to lack of child-resistant packaging, new issues of contamination, proliferation of multiple ingredient products, excessive concentration of active ingredients, and discovery of new drug-herb interactions. This review addresses contamination issues such as heavy metals, pharmaceuticals, homeopathic remedies, microbes, insects, environmental chemicals, and mis-identification of one plant for another. Toxicity issues covered include carcinogenicity, delay in seeking medical treatment when using herbs to treat serious illness, toxic components, hypersensitivity reactions, hepatotoxins, nephrotoxins, epileptogenic compounds, cardiac toxins, gastrointestinal toxins, and hematologic toxins. Common drug-herb interactions are discussed. The pharmacist plays an important role in patient education and evaluation of potential toxicities related to herbal supplements.

Herbal Hepatotoxicity: Clinical Characteristics and Listing Compilation

Herb induced liver injury (HILI) and drug induced liver injury (DILI) share the common characteristic of chemical compounds as their causative agents, which were either produced by the plant or synthetic processes. Both, natural and synthetic chemicals are foreign products to the body and need metabolic degradation to be eliminated. During this process, hepatotoxic metabolites may be generated causing liver injury in susceptible patients. There is uncertainty, whether risk factors such as high lipophilicity or high daily and cumulative doses play a pathogenetic role for HILI, as these are under discussion for DILI. It is also often unclear, whether a HILI case has an idiosyncratic or an intrinsic background. Treatment with herbs of Western medicine or traditional Chinese medicine (TCM) rarely causes elevated liver tests (LT). However, HILI can develop to acute liver failure requiring liver transplantation in single cases. HILI is a diagnosis of exclusion, because clinical features of HILI are not specific as they are also found in many other liver diseases unrelated to herbal use. In strikingly increased liver tests signifying severe liver injury, herbal use has to be stopped. To establish HILI as the cause of liver damage, RUCAM (Roussel Uclaf Causality Assessment Method) is a useful tool. Diagnostic problems may emerge when alternative causes were not carefully excluded and the correct therapy is withheld. Future strategies should focus on RUCAM based causality assessment in suspected HILI cases and more regulatory efforts to provide all herbal medicines and herbal dietary supplements used as medicine with strict regulatory surveillance, considering them as herbal drugs and ascertaining an appropriate risk benefit balance.

Herbal hepatotoxicity in traditional and modern medicine: actual key issues and new encouraging steps

Plants are natural producers of chemical substances, providing potential treatment of human ailments since ancient times. Some herbal chemicals in medicinal plants of traditional and modern medicine carry the risk of herb induced liver injury (HILI) with a severe or potentially lethal clinical course, and the requirement of a liver transplant. Discontinuation of herbal use is mandatory in time when HILI is first suspected as diagnosis. Although, herbal hepatotoxicity is of utmost clinical and regulatory importance, lack of a stringent causality assessment remains a major issue for patients with suspected HILI, while this problem is best overcome by the use of the hepatotoxicity specific CIOMS (Council for International Organizations of Medical Sciences) scale and the evaluation of unintentional reexposure test results. Sixty five different commonly used herbs, herbal drugs, and herbal supplements and 111 different herbs or herbal mixtures of the traditional Chinese medicine (TCM) are reported causative for liver disease, with levels of causality proof that appear rarely conclusive. Encouraging steps in the field of herbal hepatotoxicity focus on introducing analytical methods that identify cases of intrinsic hepatotoxicity caused by pyrrolizidine alkaloids, and on omics technologies, including genomics, proteomics, metabolomics, and assessing circulating micro-RNA in the serum of some patients with intrinsic hepatotoxicity. It remains to be established whether these new technologies can identify idiosyncratic HILI cases. To enhance its globalization, herbal medicine should universally be marketed as herbal drugs under strict regulatory surveillance in analogy to regulatory approved chemical drugs, proving a positive risk/benefit profile by enforcing evidence based clinical trials and excellent herbal drug quality.

Herbal hepatoxicity from Chinese skullcap: A case report

The use of herbal supplements has increased considerably over the last decade. We report a case of an elderly woman who began taking Move Free Advanced for arthritis, which in addition to glucosamine and chondroitin, contained two herbal ingredients, Chinese skullcap and Black Catechu. Our patient presented with significant cholestasis and hepatitis which significantly improved after discontinuation of the supplement. Since neither the patient nor the treating physician recognized this supplement as a potential hepatotoxin, she resumed taking the supplement and again suffered from considerable hepatotoxicity. Liver biopsy at that time was consistent with acute drug induced liver injury. She, once again, recovered after discontinuation of the supplement. Review of the literature confirms that Chinese skullcap has been implicated as a possible hepatotoxic agent which was demonstrated in this case.

Acute liver injury associated with the use of herbal preparations containing glucosamine: three case studies

The use of complementary and alternative medicines is becoming increasingly popular in Western society. As a result the number of reported adverse reactions is increasing. Glucosamine is a herbal remedy commonly used to ease joint pain in osteoarthritis, and only two previous reports of hepatotoxicity have been published in the scientific literature. The present report describes three patients who developed acute liver injury following exposure to glucosamine; one patient made a complete recovery on cessation of ingestion, the second developed chronic hepatitis and the third died following progression to fulminant hepatic failure. A diagnosis of glucosamine-induced hepatotoxicity was made based on the temporal relationship between onset of liver injury and glucosamine ingestion, exclusion of all other potential aetiologies and, in the two surviving cases, improvement in condition on withdrawal of the supplement.

Hepatic injury, liver monitoring and the beta-interferons for multiple sclerosis

This review explores the salient issues surrounding liver injury and liver monitoring associated with beta-interferon (IFNB) treatment for multiple sclerosis (MS). Post-marketing studies have found a higher proportion of IFNB-treated MS patients with elevated aminotransferases than reported in the pivotal clinical trials. Although the risk of severe liver injury appears small, the true incidence is unknown. Post-marketing studies have shown that the greatest period of risk for the development of liver test abnormalities appears to be in the first year of IFNB treatment. The risk also increases with the more frequently administered, higher-dosage IFNBs. Males are more likely than females to develop elevated aminotransferases (> upper normal limit), although females appear at a greater risk of severe liver injury. Of the commonly used biochemical liver tests, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AP) and bilirubin appear the most useful for routine monitoring of IFNB treatment. Whilst many other factors can affect liver test results, including obesity, alcohol, concomitant medications, co-morbidities and theoretically even MS itself, regular liver testing both prior and during IFNB therapy might help minimise Type A or dose/frequency dependent aminotransferase elevations. However, testing will probably not prevent the Type B idiosyncratic reactions which can result in severe hepatic injury; hence patients need to be aware, and to report hepatic side effects promptly.

Herbal hepatotoxicity: an expanding but poorly defined problem

Alternative therapies, including herbal remedies, are popular in the general population and even more so among patients with liver disease. The use of such products is now well established in western society and is no longer confined to traditional medicine practitioners in Asia, Africa and the Middle-East. Their perceived benefits remain generally unproven and concern about adverse effects is leading to closer scrutiny of these products. Herbal hepatotoxicity has been recognized for many years, but new agents are constantly being identified. The varied manifestations of liver injury include steatosis, acute and chronic hepatitis, hepatic fibrosis, zonal or diffuse hepatic necrosis, bile duct injury, veno-occlusive disease, acute liver failure requiring liver transplantation and carcinogenesis. Potential interactions between herbal medicines and conventional drugs may interfere with patient management. Concurrent use of such products is not often disclosed unless specifically sought after and can lead to perpetuation of the liver injury. The present review focuses on emerging herbal hepatotoxins, newer patterns of liver injury among the older agents and provides an updated tabulation of the adverse effects of major herbal hepatotoxins. Key issues of diagnosis and prevention of this growing problem are addressed. Continued public education, physician awareness and more stringent licensing are required to tackle this growing problem.