Herbal medicines, adverse reaction

The Yellow Card Scheme, at first restricted to receive reports from doctors, dentists and coroners, has been gradually expanded to receive reports from other sources. From October 1996, the Scheme was extended to include reporting of suspected adverse reactions to unlicensed herbal remedies. In April 1997, the Yellow Card Scheme was further extended to include hospital pharmacists as recognised reporters of suspected ADRs. In addition, there are specially targeted extensions of the Scheme such as adverse reactions to HIV medicines and adverse reactions in children. Over the period, the Scheme has been gradually extended further to receive reports from community pharmacists and in October 2002, from nurses, midwives and health visitors. 

D Arcy PF. Adverse reactions and interactions with herbal medicines. Part 2. Drug interactions. Adverse Drug React Toxicol Rev 1993 12 147-162. 

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. 

In a 5-year toxicological study of traditional remedies and food supplements carried out by the Medical Toxicology Unit at Guy s and St. Thomas Hospital, London, 1297 symptomatic enquiries by medical professionals were evaluated (28). Of these, an association was considered to have been confirmed, probable, or possible in 12, 35, and 738 cases respectively. Ten of the confirmed cases were related to Chinese or Indian herbal remedies. As a result of these findings, in October 1996 the UK Committee on Safety of Medicines extended its yellow card scheme for adverse drug reaction reporting to include unhcensed herbal remedies, which are marketed mostly as food supplements in the UK (the scheme had always apphed to hcensed herbal medicines) (29,30). This was an important milestone in herbal pharmacovigilance. 

A retrospective analysis of aU adverse events related to herbal medicines and dietary supplements reported to the California Poison Control System has given data on the risks of the adverse effects of herbal medicines (112). Between January 1997 and June 1998, 918 calls relating to such supplements were received. Exposures resulting in adverse reactions occurred most often at recommended doses. There were 233 adverse events, of which 29% occurred in children. The products most frequently implicated were zinc (38%), Echinacea (8%), witch hazel (6%), and chromium picolinate (6%). Most of the adverse events were not severe and required no treatment hospitalization was required in only three cases. 

Chan TY, Chan AY, Critchley JA. Hospital admissions due to adverse reactions to Chinese herbal medicines. J Trop Med Hyg 1992 95(4) 296-8. 

Hohmann, H. and Koffler, K. 2002. Risk of adverse reactions from contaminants in Chinese herbal medicines minimized by using quality products and qualified practitioners. Int. J. Environ. Health Res. 12, 99-100 author reply 101. 

A person s use of alternative medicine must be solicited. Many herbal remedies were once wisely abandoned because of their common adverse reactions. Comfrey tea is a common cause of hepatocellular damage. As in the case of the Chinese remedy jin bu huan, or as in the case of the more elegantly presented chaparral capsules containing grease wood leaves, the end of therapy with these types of agents is occasionally severe disability or death from fulminant hepatic failure." Pennyroyal oil, maragosa oil, and clove oil cause a dose-related hepatotoxicity." ... 

As a consequence of the toxicity related to the presence of aristolochic acid in plant preparations, several health institutions, such as the US Food and Drug Administration, Therapeutic Goods Administration have recently published safety information to prevent further cases of intoxication (information available at web address http //www.cfsan.fda. gov/ dms/ds-bot.html) [471], So detecting aristolochic acids in plant species that could be used in herbal remedies, and also in herbal preparations of uncertain composition, has attracted great priority in recent years to help prevent future adverse reactions. Aristolochic acids present in medicinal plants or herbs are analyzed by soxhlet extraction followed by TLC in the Chinese pharmacopoeia [412]. Another report used multiple ultrasonic extraction followed by HPLC analysis [472]. Ong s laboratory reported a method using a home made pressurized liquid extraction (PLE) system in dynamic mode to extract aristolochic acid in medicinal plants, followed by gradient elution HPLC [473]. Several scientific communities described various analytical methods for... 

Make sure that the patient thinks of herbs as medicine that is less potent than conventional medication. However, adverse reactions can occur if conventional medication is taken with herbal therapy. For example, some conventional medication may act faster than expected when combined with herbal therapy. 

A systematic review of herbal medicines for lower back pain identified two trials of topical cayenne monopreparations and reported that adverse events in cayenne treatment groups were inflammatory contact eczema, urticaria, minute hemorrhagic spots, and vesiculation or dermatitis. In one trial, 15 adverse events were reported in the cayenne group and 9 in the placebo group (Gagnier et al. 2007). In a clinical trial of a topical capsicum plaster or placebo, localized adverse drug reactions were found in 7.5% of the patients on capsicum and 3.1% on placebo (Frerick et al. 2003). 

The use of natural products such as chitosan [2] and natural dyes [3-4] for antimicrobial finishing of textile materials has been widdy reported. Other natural herbal products such as Aloe Vera, Tea Tree oil. Eucalyptus oil, Tulsi leaf (Pcimum basilicum) extracts etc. can also be used for this purpose, as there is a vast source of medicinal plants with active antimicrobial ii dients. Althoi there are many natural products rich in antimicrobial agents but tiie work on the exploration of their use in textiles is very limited and not well documented. The relatively lower incidence of adverse reactions to herbal products compared to modem synthetic pharmaceuticals, coupled with their reduced cost, can be... 

The Constituents of Medicinal Plants was never designed as a pure exposition of chemical structures—I leave that to the analytical chemists. My belief is that the structures give us an important insight into the way herbal medicines act, and are a way of rationalising many of the traditional applications that have been passed down over the centuries. The structures also give us valuable information into the potential for adverse reactions and interactions with pharmaceutical drugs. 

Pharmacovigilance in complementary and alternative medicine Pharmacovigilance in complementary and alternative medicine has attracted much attention worldwide. The awareness of the need for surveillance of adverse reactions to natural health products has stimulated the implementation of a reporting system for suspected adverse reaction in Italy From April 2002 to March 2007, 233 spontaneous reports of suspected adverse reactions to natural health products were collected. A large proportion of the suspected adverse reactions were serious hospitalization was reported in 35% of cases 6% reported life-threatening clinical events, and there were two fatal events. Most of the reported cases involved herbal products (66%) 21 reports were associated with 27 homeopathic preparations, most of which contained a mixture of substances 14 reports attributed the suspected reactions to products containing propolis. 

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