Book excerpt: The medical use of marijuana is surrounded by a cloud of social, political, and religious controversy, which obscures the facts that should be considered in the debate. This book summarizes what we know about marijuana from evidence-based medicineâ€"the harm it may do and the relief it may bring to patients. The book helps the reader understand not only what science has to say about medical marijuana but also the logic behind the scientific conclusions. Marijuana and Medicine addresses the science base and the therapeutic effects of marijuana use for medical conditions such as glaucoma and multiple sclerosis. It covers marijuana's mechanism of action, acute and chronic effects on health and behavior, potential adverse effects, efficacy of different delivery systems, analysis of the data about marijuana as a gateway drug, and the prospects for developing cannabinoid drugs. The book evaluates how well marijuana meets accepted standards for medicine and considers the conclusions of other blue-ribbon panels. Full of useful facts, this volume will be important to anyone interested in informed debate about the medical use of marijuana: advocates and opponents as well as policymakers, regulators, and health care providers.