Setting Standards of Safety & Efficacy of Herbal Drugs

Article excerpt

Byline: Magdalena C. Cantoria, Ph.D. Academician

NIYUG-NIYOGAN, ampalaya, lagundi, and sambong. These are just some of the herbal medicines that our ancestors used as traditional medicines. Now with long folkloric usage, accumulation of anecdotal evidence, and increasing documentation of scientific studies about their effectiveness, medicinal herbs are regaining wide public and scientific interest.

Herbal drugs consist of plant products that may be whole plants (nonwoody plants botanically referred to as "herbs") or parts of plants (like ulasimang bato herb, bayabas leaf, niyugniyogan seed, and luya rhizome). These may be parts of woody plants (barks of dita and duhat) or miscellaneous plant products such as secretions (gums, fixed and volatile oils), exudates (oleoresins and resins), and juices (of akapulko leaf and sabila). Herbal drugs are often used to treat chronic diseases or to attain or maintain improved health condition.

Herbal medicine, also referred to as traditional medicine, is practiced throughout the world and has developed into a science-based practice (termed phytotherapy) in some European countries. In Germany, herbal medicines have a special status beginning with the Imperial Decree of 1901 that permitted the trade of many botanical drugs outside pharmacies. Through the following years, drug laws were passed requiring a review of all conventional drugs as well as phytomedicines in the market at that time to assure that they met appropriate standards for quality and purity.

In 1978, Commission E, an expert committee composed of health professionals with expertise in their respective therapeutic areas, was established to review and evaluate the safety and efficacy of herbal drugs and preparations. Members of the committee actively collected bibliographic data on the herbal drugs being reviewed, including their traditional use, chemical data, experimental pharmacological and toxicological studies, clinical studies, field and epidemiological studies, patient records submitted from physiciansa files, and additional studies including unpublished proprietary data submitted by manufacturers.

By 1995, the Commission E had scientifically evaluated more than 300 herbs and about 400 herb preparations for safety and efficacy. The evaluation results, reviewed by the Commission members, other scientists, scientific associations, universities, and other experts, were published as monographs. The monographs, originally printed in German, were translated into English by the American Botanical Council (ABC) and published in 1998 under the title "The Complete German Commission E Monographs a" Therapeutic Guide to Herbal Medicines." The ABC expanded the monographs of the most commonly used herbs in the United States and published these in 2000 under the title "Herbal Medicine a" Expanded Commission E Monographs."

The Commission E monographs are therapeutic monographs and do not detail standards for identity, purity, and quality found in pharmacopoeial monographs. Based on the safety and efficacy of each plant drug as supported by controlled clinical studies, the Commission E divided the herbs into "Approved" and "Unapproved" herbs.

World Health Organization monographs

In 1986, the World Health Organization (WHO) was requested by member states to compile a list of the most widely used and important medicinal plants in all WHO regions and prepare monographs establishing standards for their safe and effective use in national health care systems. WHO published the guidelines for assessing herbal medicines in 1991. Professors N.R. Farnsworth, H.H.S. Fong, and G.B. Mahady and pharmacognosists of the WHO Collaborating Centre for Traditional Medicine at the College of Pharmacy, University of Illinois, drafted and reviewed the first volumes of monographs. The content of the monographs was obtained by a systematic review of scientific literature from 1975 to 1995 and reviewed by participants in the WHO Consultation on Selected Medicinal Plants held in Munich, Germany in 1996. …