An adult patient on a first-generation antipsychotic develops a shuffling gait and tremor. What course of action is indicated?

• A. Administer an anticholinergic medication
• B. Increase the dose of the antipsychotic
• C. Add a second-generation antipsychotic immediately
• D. Discontinue the antipsychotic

Answer: (A)

Movement side effects from a first-generation antipsychotic come from dopamine blockade in the nigrostriatal pathway, which tips the scale toward acetylcholine and produces parkinsonian symptoms such as tremor and a shuffling gait. The best immediate action is to give an anticholinergic medication (for example benztropine or trihexyphenidyl), which helps restore balance in the striatum and reduces extrapyramidal symptoms. Increasing the antipsychotic dose would worsen these motor effects because it further blocks dopamine. Adding another antipsychotic right away could complicate management and may not promptly relieve the parkinsonian symptoms. Discontinuing the antipsychotic is not the first step to treat the EPS, as the psychotic illness still needs management and EPS relief is typically achieved with an anticholinergic or a switch to a medication with a lower risk of EPS after addressing the acute symptoms.