Although many nail disorders have been associated with drug intake, most reports are anecdotal. Most nail changes caused by drugs are the outcome of acute toxicity to the nail epithelia; nail symptoms depend on which nail structure is damaged. The most com-mon symptoms include Beau's lines/onychomadesis, melanonychia, onycholysis, and periungual pyogenic granulomas. Drug-induced nail abnormalities are usually transitory and disappear with drug withdrawal, but sometimes persist over time. This article reviews drugs that have been consistently associated with nail abnormalities.