Herbal pills – english blog

Adulteration
Most of the literature on the toxicity of Chinese herbal medicines consists of case reports describing the effects of using traditional medicinal agents adulterated with biomedical pharmaceuticals. In the United States, this has sometimes involved pharmaceutical agents that are no longer approved for human use. Adulteration with agents such as heavy metals may present the greatest risk to patients who use Chinese herbs.
Adulteration of prepared medicines imported from China and Taiwan is widespread. In some instances, these products are legitimate in their country of origin. In others, an ambitious or unscrupulous manufacturer has incorporated a pharmaceutical agent to enhance the apparent effects of the prepared herbs. Comparatively harmless examples involve the common adulteration of the famous herbal remedy for colds Yin Qiao San with acetaminophen. More harmful examples involve herbal medicines adulterated with large amounts of cortisone and/or nonsteroidal anti-inflammatory drugs and sold as arthritis remedies. The potential to confuse the consumer is increased because certain stores in American Chinatowns sell biomedical pharmaceuticals manufactured in China alongside prepared herbal remedies.
Results of a study of arthritis remedies and analgesics sold in herb stores and Chinese medicine clinics in Taiwan showed that 30% of items sampled contained drugs,4 including acetaminophen, ibuprofen, and phenylbutazone. In New York, several Chinatown herb stores have sold dangerously adulterated substances, including Madam Pearl’s Cough Syrup. This product, which contains codeine, has been an object of regulatory concern since at least 1988 when it appeared on lists provided by the Department of Health Services in California.
Other adulterated preparations found in herb stores, grocery stores, and through the mail, include Black Pills, Chui Fong Tou Koo Wan, and Cow’s Head Tong Sui Pills. Chui Fong Tou Koo Wan is sold for the treatment of rheumatism and arthritis. It contains, among other ingredients, phenylbutazone, diazepam, and lead. In 1995, Gertner et al described cases involving five patients from Minnesota with complications from the use of herbal arthritis remedies.5 In all cases, the pills were found to contain diazepam and mefenamic acid, both of which can have severe side effects. The public and regulatory agencies, such as the Food and Drug Administration, are increasingly aware that many illegally imported, but commonly used, prepared Chinese herbal medicines contain biomedical pharmaceuticals. Most of these additions are not represented on the product label, raising the possibility of overdose or other serious consequences.
Toxicity and adverse effects
Adverse events associated with herbal medicines typically result from long-term use at inappropriate dosage levels, the use of certain highly toxic substances, and hypersensitivity reactions.
Aconite is probably the most widely used of the highly toxic substances within the Chinese materia medica. The forms of this plant that are sold in herb stores and used in prescriptions are treated with heat, water, and vinegar to degrade the toxic alkaloid and to eliminate any significant toxicity. Untreated materials are occasionally used, however, and reports of toxicity have resulted.
Many cases of poisoning with aconite contained in the herbal treatments chaun wu and cao wu have occurred in China and Hong Kong. A study at one Hong Kong hospital between 1989 and 1991 identified eight patients with signs of poisoning from these substances, including nausea, vomiting, low blood pressure, and ventricular extrasystoles.6 Instances of poisoning are probably underreported, so these cases may be the tip of the iceberg. The Chinese government was concerned enough to act to impose controls on prescribing aconite.
The Chinese medicine Jin Bu Huan was implicated in three cases of overdose in children.7,8 The children were hospitalized with life-threatening bradycardia, and central nervous system and respiratory depression. All recovered after receiving intensive medical care. The product has been formally removed from the commercial market, although it is still available in New York.
A well-known case of reported herbal toxicity has come to be known as “Chinese herbs nephropathy.” Seventy women who were patients at a Belgian weight loss clinic from 1991 to 1992 presented with interstitial renal fibrosis and end-stage renal failure.9,10 The Chinese herb Aristolochia was implicated in their renal damage. This species of herb contains aristolochic acid, which is toxic to laboratory animals in an extracted and injected form. Debate is ongoing, however, as to the actual relevance of Aristolochia in nephropathology.
Although Chinese herbal medicines are used commonly, the overall known incidence of adverse reactions appears relatively low. In an 8-month prospective study of patients admitted to two general medical wards at one hospital in Hong Kong, only 3 of 1,701 patients (0.2%) were hospitalized because of adverse reactions to Chinese herbal medicines.11 These reactions were life-threatening in two cases (dazao-induced angioneurotic edema and licorice-induced hypokalemic periodic paralysis).
Herb-drug interactions
The possibility of herb-drug interactions has been raised,12 but reports that are directly pertinent to Chinese herbal medicine are scant and often anecdotal. Instances of well-researched and well-understood interactions are rare.
The Table provides well-documented examples of commonly used Chinese herbs that have well-understood side effects or the potential for drug interactions. Given the differences between herbs and single-molecule pharmaceutical preparations, dosage level and duration of use are important in assessing risk. A compound containing licorice, ephedra, or even processed aconite presents little risk to a patient and is unlikely to interact immediately with a given pharmaceutical. Large quantities, incorrect preparation, or long-term use of a compound, however, may cause problems to occur.