Herbal medicines in the treatment of psychiatric and neurological disorders

Abstract

Herbal medicines include a range of pharmacologically active compounds: in some cases it is not well understood which ingredients are important for a therapeutic effect. The supporters of herbal medicine believe that isolated ingredients in the majority of cases have weaker clinical effects than whole plant extract, a claim that would obviously require proof in each case. Generalizations about the efficacy of herbal medicines are clearly not possible. Each one needs systematic research including a variety of animal studies and also randomized clinical trials. Indeed, clinical trials of herbal medicines are feasible much in the same way as for other drugs (Schulz, Hansel & Tyler, 1998). Numerous randomized clinical trials of herbal medicines have been published and systematic review and meta-analyses of these studies are available. Many of today's synthetic drugs originated from the plant kingdom, and only about two centuries ago the major pharmacopoeias were dominated by herbal drugs. Herbal medicine went into rapid decline when basic and clinical pharmacology established themselves as leading branches of medicine. Nevertheless, herbal medicine is still of interest in many diseases in particular psychiatric and neurological disorders. There are some reasons for this: (1) participants are dissatisfied with conventional treatment, (2) participants want to have control over their healthcare decisions, and (3) participants see that herbal medicine is congruent with their philosophical values and beliefs (Astin, 1998). It has been reported that most participants with a mental disorder sought herbal medicine treatment for somatic problems rather than for their mental and emotional symptoms and the best example is somatic symptoms of depression.