This chapter discusses various medicinal poisons in detail. The action, signs and symptoms, treatment, and postmortem findings of various medicinal poisons such as paracetamol, antipsychotic drugs, antihistaminics, tricyclic antidepressants, benzodiazepines, acetylsalicylic acid, and chloral hydrate, are discussed. Paracetamol (PCM), after absorption, is metabolized by glucuronidation and sulfation and by cytochrome P450 oxidase system. For a suspected case of poisoning with antipsychotic drugs, administration of diphenhydramine results in resolution of dystonia or oculogyria. In case of antihistaminics poisoning, there is severe central nervous depression, and death results from respiratory failure or cardiovascular collapse. Flumazenil, an antidote of benzodiazepines, selectively blocks the central effects of benzodiazepines by competitive inhibition. Chloral hydrate poisoning can be treated by gastric lavage with alkaline solution, hemodialysis, and flumazenil 0. 1 mg as infusion upto a total of 3 mg.