Medical toxicology, which encompasses the pathophysiology, diagnosis, and treatment of clinical problems related to poisoning and drug intoxication, has in the past decade become an established subspecialty with demonstrated breadth and depth of knowledge. Medical toxicologists treat patients with acute drug overdoses, as well as those poisoned by industrial chemicals, native or exotic snakes, wild mushrooms, herbs, and alternative medical products. Medical toxicologists are emergency physicians, internists, pediatricians, occupational physicians, clinical pharmacologists, specialists in laboratory medicine, nurses, and clinical pharmacists. They direct poison-control centers, drug-detoxification centers, research units in clinical pharmacology, and public health agencies.