Psychotropic drugs dominate the mental healthcare landscape. This is despite contention over their proposed mechanism of action, concerns for their adverse effects, and questionable effectiveness, especially over the long term. Mental health nurses are routinely involved in administering psychotropic drugs, observing for and managing adverse effects, and providing information and support to people prescribed these agents. This critique explores the current understanding of the mechanism of action for psychotropic drugs, evidence for their effectiveness, adverse effect burden and implications for long term use. The role of mental health nurses in deprescribing and supporting people to discontinue treatment is considered.