Herbal therapy: what a clinician needs to know to counsel patients effectively.

The use of herbal medicine in the United States has been increasing at a steady pace over the past decade. Most recent estimates suggest that the US population spends $5 billion per year for herbal supplements alone. Herbal supplements are receiving increasing exposure through national media, in lay journals, and more recently in the scientific press. Interest in herbal medicine has been facilitated by multiple factors, including the perception that pharmaceutical medications are expensive, overprescribed, and often dangerous. Alternatively, herbal medicine is often perceived as being "natural" and is therefore considered safe. While the growth of the herbal medicine industry in the United States can probably not continue at this accelerated pace indefinitely, there is little indication of any major slowing. Therefore, patients will continue to use herbal medications. Knowledge of these preparations (including their potential benefits and risks as well as their ability to interact with pharmaceutical medications) will enable physicians to provide a balanced and objective view to patients seeking information on herbal therapy.