As a child psychiatrist who treats adolescents with substance dependence disorders, I was very pleased to read this well written scientific review from Dr. Iversen, a pharmacologist. It really does appear to be reasonably unbiased on the question of whether cannabis has medicinal value, and attempts to review the scientific evidence in a rational way. However, the scientific evidence so far is nowhere near the level of proof of safety and efficacy required to get new medications approved for use by the FDA, and Dr. Iversen conveniently ignores this vital issue.
Additionally, he glosses over the very real and known physical and mental health risks associated with heavy chronic marijuana smoking. ... His perspective is that of scientist concerned with the effects of THC, rather than mine, as a physician concerned with the mental and physical health of children who seek my help. I generally agree with his conclusions, that cannabis may have some potential for therapeutic use if we can find a way to dissociate its adverse effects and its habit-forming potential from its therapeutic effects. However, the current science is far from achieving such a goal. It concerns me that Dr. Iversen has left a very vital branch of biomedical science out of his review, namely, the epidemiology, comorbidity, and health consequences of cannabis abuse and dependence. While it is true that most people who smoke pot occasionally are probably not going to become addicted or escalate use into more dangerous drugs, it remains the major "gateway drug" by which adolescents are introduced into the addictive downward spiral that can destroy their lives, if they are one of the unfortunate who are biologically predisposed to addiction. The failure to review the science of cannabis dependence and the substantial scientific literature on the psychobiology of addictive behavior is the only major shortcoming of an otherwise fascinating book.

This is a highly readable volume that delivers a superb overview of the history, pharmacology and sociology of marijuana. Although the non-scientist may find it tough going in a few places, Iversen does an admirable job of presenting the technical issues with clarity. More importantly, the objectivity is unassailable. If you are looking for the book to tell you that marijuana smoking is perfectly safe you will be disappointed. Equally, if you seek justification of hysterical anti-drug rhetoric you will be unfulfilled. But, if you want to be educated and informed so that you can make your own judgement this is a great place to start. Highly recommended!

A superb, accessible, scientific assessment of the pharmacology. medicinal uses, health consequences, and recreational effects of the most popular illicit drug in the world. Iversen stays as objective as possible in his discussions of this highly volatile and political topic. He puts nails in the coffins of many marijuana myths, including those related to alleged chromosomal damage and dramatic increases in THC content. He offers keen historical perspectives, and depicts difficult scientific ideas with ease.