Interest in and usage of herbal preparations as alternatives to pharmaceuticals has exploded in recent years. Having a complete herbal reference on hand is now absolutely necessary for doctors and other healers when a patient wants to add herbs–let’s say St. John’s wort–to his drug regimen. Should the patient stop taking the Paxil he’s been on for depression, and if so, how long must he wait before he can start taking the St. Johns wort, and what’s the recommended dosage?The PDR for Herbal Medicines will go a long way towards answering such questions. The physician in this case would learn, after consulting the PDR, that “St. John’s wort taken concomitantly with an SSRI … may lead to an increased effect and possible toxicity ‘serotonin syndrome’, e.g.,sweating, tremor, flushing, confusion and agitation.” The same physician will also learn that the German Federal Health Authority’s Commission E, which has studied the effects of hundreds of herbs,approved St. John’s wort for depressive moods, among other conditions.For more information, the physician can read about the trade names, descriptions of all the medicinal parts of the plant, actions and pharmacology (including the compounds and their effects, with citations), the results of clinical trials, contraindications, precautions and adverse reactions (photosensitization is a biggie for St. John’s wort), dosage information, and a complete list of literature citations.The second edition of this mammoth guide includes over 100 entries more than the first, bringing the total to more than 700. Additions include a selection of Asian herbs, such as Buplerum Chinese (also known as Chinese thoroughwax), which is used in Chinese medicine as an anti-inflammatory, and homeopathic preparations; a directory of manufacturers (with Internet addresses when available), a safety guide (don’t use kava kava while nursing), and more. There’s even a section that lists unproven uses for each herb. But make no this is a mainstream reference that relies on scientific proof above all. Therefore, this is not a guide for everyone, but for scientific and medical reference, it’s a helpful and comprehensive resource, and even those who push the herbal envelope will find much valuable information here. –Stefanie Durbin