Chinese herbal prescriptions are carefully composed mixtures of individual herbs. The proportions are specific to each person, and they are easily modified to meet the needs of the individual. Herbs may be administered in a raw form in which they must be cooked by the patient, or in a convenient powdered form that can be mixed in warm water. Many formulas are now available in pill form.
I only prescribe herbs from companies that guarantee quality control and safe manufacturing procedures, including testing for heavy metals. To read about safety precautions in herb manufacturing check out Crane Herb Company.