Herbal products hepatotoxicity

Herbal medicines are becoming more and more popular, and indeed some herbal products may be considered to benefit people with liver disease, e.g. Silybum marianum (milk thistle), Picrorhiza kurroa, Phyllanthus, etc. Herbal hepatotoxicity is increasingly being recognised, for example, with kava kava, black cohosh, and many traditional Chinese remedies. The range of liver injury includes minor transaminase elevations, acute and chronic hepatitis, steatosis, cholestasis, zonal or diffuse hepatic necrosis, veno-occlusive disease and acute liver failure. In addition to the potential for hepatotoxicity, herb-drug interactions may affect the safety and efficacy of concurrent medical therapy [15]. 

A review of adverse events related to herbal medicines reported in the medical literature from 1992 to 1996 has been compiled. This report highlights cases of hypersensitivity reactions, hepatotoxic reactions, and various types of renal damage associated with various herbal products. Some Chinese herbal preparations appear to be notorious for causing nephropathy.One of the more infamous adverse events related to the consumption of a dietary supplement was associated with the amino-acid L-tryptophan, touted for it s ability to reduce pain and promote sleep. 

Chaparral can be found in health food stores as capsules and tablets and is used as an antioxidant and anti-cancer herbal product. Leaves, stems and bark in bulk are also available for brewing tea. However, this product can cause severe hepatotoxicity. Several reports of chaparral-associated hepatitis have been reported. A 45-year-old woman who took 160 mg of chaparral per day for 10 weeks presented with jaundice, anorexia, fatigue, nausea and vomiting. Liver enzymes and other liver function tests showed abnormally high values (ALT 1611 U L- AST 957 U L, alkaline phosphatase 265 U L, GOT 993 U L and bilirubin... 

Currie, B.J., and A.R. Clough. 2003. Kava hepatotoxicity with Western herbal products Does it occur with traditional kava use Med.. Aust. 178(9) 421-422. 

Cao, Y., S.M. Golegate, and J.A. Edgar. 2008. Safety assessment of food and herbal products containing hepatotoxic pyrrolizidine alkaloids Interlaboratory consistency and the importance of N-oxide determination Phytochem. Anal. 19(6) 526-533. 

Liver In recent years, there have been many reports of hepatotoxicity associated with herbal products used for weight reduction. These products, which are sold as dietary supplements, do not usually undergo safety tests before they are marketed [48 ]. 

Black cohosh has been one of the most studied herbal remedies for vasomotor symptoms, and it has not demonstrated a substantial benefit over placebo. The mechanism of action, safety profile, drug-drug interactions, and adverse effects of black cohosh remain unknown. In non-placebo-controlled trials conducted for 6 months or less, black cohosh demonstrated a small reduction in vasomotor symptoms. It has not been shown to be effective for vasomotor symptoms in women with breast cancer.33 There have been case reports of hepatotoxicity with the use of black cohosh.36 Caution should be exercised when considering the use of this product, especially in patients with liver dysfunction. 

Rttler, M.H., Ernst, E. Systematic review Hepatotoxic events associated with herbal medicinal products. Alim. Pharm. Ther. 2003 18 451-471... 

Mistletoe is sometimes assumed to have hepatotoxic potential, based on a case report of hepatitis due to an herbal combination product claimed to have had mistletoe as one of its ingredients (3). However, the allegation that mistletoe was the probable cause of the illness has been rightly criticized, inter alia because the botanical material was not authenticated. The incriminated product also contained skullcap, which is hepatotoxic. 

Although the horse appears to be refractory to the hepatic effects of most NSAIDs, their hepato-toxic potential should be considered, especially when they are concomitantly administered with other potentially hepatotoxic agents, such as fluoroquinolones, potentiated sulfonamides or anabolic steroids. In addition, many herbal preparations are potential hepatotoxic agents and clients may administer these compounds concurrently with prescribed NSAIDs without consulting their veterinarian. Echinacea and kava kava products, for example, are reported to be potential hepatotoxins and both are used in herbal remedy products that claim to produce calming or sedating effects in horses (Abebe 2002). 

An 82-year-old man with fatty liver who regularly used laxatives (herbal and nonherbal) over the course of the prior 20 years developed hepatotoxicity with elevated levels of liver enzymes after the commercial herbal laxative that he had been taking changed formulas to include an extract of boldo as one of the ingredients in a multi-ingredient product. Liver enzymes returned to normal after cessation of the herbal laxative (Piscaglia et al. 2005). 

---