The aim of our pocket guide is to provide "at a glance" key points for the busy clinician to access when dealing with a patient, presenting the pathologies pertinent to each drug, and options for the treatment of substance dependence. In the "The Pocket Guide to Drugs and Health" we have extended the drugs covered to include the major licit psychoactive drugs: alcohol, hypnosedatives, and nicotine & tobacco.Each major drug class is examined individually (Alcohol, Cannabis, Hallucinogens, Hypnosedatives, Nicotine & tobacco, New Psychoactive Substances, Opioids, Psychostimulants). In each chapter we present information on withdrawal and dependence syndromes, toxicity, the effects upon major organ systems, and psychiatric morbidities. There are also dedicated chapters on the medical complications of injecting drug use, and the treatment of drug dependence. It is our hope that this book will form a core pocket guide for medical practitioners, physicians in training and nurses.