This is a work in progress, but I'll begin here: Dr. Perrine has successfully written a very readable reference work. I read it from cover to cover over about a month long period, normally books like this are exceedingly dry, but this book is actually fun to read. It has a lot of obscure facts about drugs that I've never heard (and I consider myself well-informed), and it is extremely well referenced. It is divided into chapters based on drug class: benzodiazepines and related sedatives, stimulants, hallucinogens, opiates, and cannabinoids/dissociatives, with the 'legal highs' mixed in throughout. It is technical enough that a couple of introductory courses in organic chemistry are necessary to follow the reaction schemes...obviously the more training the reader has the easier these will be to follow. I'm not a chemist, but I am a chemistry student and at many points in the book I had to ask questions about certain things of my chemistry friends and/or reference wikipedia or my O-chem text.
The chemistry naive reader need not fret, large portions of the book are still easy reading and it would be well worth their time to give it a try. Chemists and pharmacologists are encouraged to read it as well, in part because it is scientifically rigorous, and in part because the author readily admits in the introduction that the work is not perfect and might contain mistakes, which, if found, should be noted and brought to his attention. He puts his contact information in there, which I really like. I enjoyed reading this book and I think other Drugs Forum members will as well.