Therapeutic use of plants for the treatment of human illnesses dates back over many millennia. Evidence of their effectiveness in the diagnosis, cure and prevention of disease states exists in every culture throughout the world. Today "traditional medicine," characterized by the use of herbs and other natural products, still remains a regular component of health care in countries such as China, Japan, India, South America and Egypt. In the United States, where scientific methodologies are considered the foundation for effective and safe health care, this form of "alternative therapy" is not quite as readily accepted by most physicians. Since the last decade, however, herbal products used as therapeutic remedies are rapidly gaining popularity among health consumers.
Is Phytomedicine indexed in the IDIS Database ?
There is a wealth of nonscientific herbal medicine information readily available to the health consumer. Access to scientific literature is crucial to the pharmacist for his or her role as a drug information provider. The pharmacist, among all health care practitioners, is in the best position to provide information about "drug" safety and effectiveness. If an herb is used as a therapeutic agent, it should be considered a drug.
A "global search" with the terms Herbal Medicine* entered in the Global field of the Field Search template retrieves 369 Hits* (IDIS file 1985 through October 1997).
Search terms entered in the Global field are cross referenced and searched in all fields including the Abstract field. This search is not specific but estimates IDIS coverage of the herbal medicine literature and provides examples of how herbal medicine is indexed.
Glancing at the search results, one can see that all aspects of herbal medicine are covered: overview, side effects, adulteration, pharmacokinetics, efficacy, interaction. Sixty-three percent of the 369 citations are reports or case reports. Close to twelve percent of the articles are classified as studies with only 8 randomized controlled studies. Several review articles and book reviews give basic information useful to the pharmacist with limited background in the field of herbal therapy (Bartram; Newall; Phillipson; Tyler, 1995, 1996). The result of this search is not surprising; most of the scientific phytomedicinal research is being done in Western European countries, especially in Germany.
A search conducted with the same terms against IDIS 1966-1984 database yields only 24 citations.
The substantial difference in the number of citations found between the two files (1985 through October 1997 and 1966-1984) can be explained by an increased awareness in phytomedicine by the medical community. Herbal Medicine was added as a valid drug term to the IDIS drug vocabulary in 1981 as interest increased in this form of alternative therapy. Since 1996, the addition of European Journal of Herbal Medicine and American Journal of Chinese Medicine to the IDIS journal list has contributed 31 citations to the database.
Which Phytomedicinals are Indexed in IDIS Database?
Thousands of herbal products are available worldwide. In some countries, herbal medicines are perceived as drugs and can be bought over the counter or prescribed by physicians. In the United States, herbal preparations are not classified as drugs by the Food and Drug Administration. In Germany, results of pharmacological research, clinical studies and bibliographic searches must be submitted to a special commission of the German Ministry of Health, Commission E, for risk-benefit evaluation before marketing authorization is granted.
In France, the sale of herbal medicines is under less stringent but more pragmatic regulations; an herb is considered a safe and effective drug if it can be "traditionally" proven safe and effective. Euphytose, a valerian based mild sedative drug introduced in France in 1927 can be 65% reimbursed by the "Securite Sociale" when it is prescribed by a physician, but it can also be bought without a prescription. Not all herbal medicines are reimbursable. Lenicalm, a linden tree and hawthorne composition, on the market since 1990 for mild insomnia is not reimbursable. In the United States, herbal preparations are not classified as drugs by the Food and Drug Administration (FDA). They are classified as "dietary supplements" with a few exceptions such as Capsicum, Elm Bark, Juniper, Karaya Gum, Psyllium and Witch Hazel. Over the years the United Stated Pharmacopoeia has included more than 600 herbals in its compendium.
Side Effects of Phytomedicine:
Little is known about phytomedicine safety. There has been an increase in the number of side effects reported in the literature. Many cases, however, could have gone unreported because herbal medicine is usually self-prescribed and oftentimes ignored by health practitioners during the patient's care. Identifying adverse effects is further hindered because it is not always possible to assess the quality of certain herbal medicinal products.
By comparing the results of the searches, one can see that sixty-four percent of the citations found in IDIS reported a phytomedicine-induced side effect.
The potential risk of an herbal medicine interacting with a prescribed drug is also a concern with the increased use of phytomedicines. Recently, several interactions have drawn the attention of the medical community.
Janetzky and Morreale reported a probable interaction between ginseng, one of the most popular herbs with multiple health claims, and warfarin, a drug with numerous well-recognized drug-drug interactions.
Several other drug-herbal interactions between Siberian ginseng and digoxin, ginseng and phenelzine and other MAO inhibitors were found in IDIS.
A clinically significant interaction between warfarin and an herbal medicine containing Salvia miltiorrhiza roots causing clotting abnormalities was reported by Yu. A randomized, crossover study performed on eight healthy subjects reported no significant pharmacokinetic interactions between levofloxacin and three selected traditional herbal medicines. No differences were found in levofloxacin plasma concentration, area under the curve, terminal elimination half-life or renal clearance (Hasegawa).
A randomized, crossover drug-herbal interaction study was conducted in 22 healthy volunteers to investigate the effect of three major Chinese herbal medicines containing 60 to 66 mg of glycyrrhizin on the pharmacokinetics of prednisolone. The effect on prednisolone pharmacokinetics differed between the three preparations although they contained a similar amount of glycyrrhizin (Homma).
Conclusion:
Eighty percent of the world population is using some form of herbal medicine. In 1990, in the United States, one out of three Americans sought a complementary or alternative form of medicine. In 1992, the Office of Alternative Medicine, a component of the National Institutes of Health was created to "facilitate the evaluation of alternative medical treatment modalities" and to serve as a "public information clearinghouse"
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