Delayed-Onset Cariprazine-Induced Akathisia: A Case Report

This case report describes the clinically underrecognized manifestation of delayed-onset akathisia induced by cariprazine occurring 10 weeks after treatment initiation. The secondary objective was to discuss potential pharmacokinetic and pharmacodynamic mechanisms of the drug-induced side effects.

A retrospective review of the patient's medical and psychiatric history was performed in addition to a comprehensive literature review.

A 42-year-old female with bipolar disorder and generalized anxiety disorder presented to the emergency department on 3 separate occasions with severe restlessness and insomnia, commonly attributed to her previous history of anxiety. Although initial treatment with lorazepam provided subjective symptom relief, the underlying cause persisted. Psychiatry consultation led to a diagnosis of antipsychotic-induced akathisia and administration of diphenhydramine resulted in rapid improvement. The offending agent, cariprazine, was discontinued, resulting in sustained symptom resolution.

This case highlights the challenge of distinguishing akathisia from primary anxiety disorders, in addition to considering this diagnosis beyond the initial treatment period. Akathisia symptoms most commonly present within 4 weeks of initiation or titration of antidopaminergic treatment. However, this timeline may be delayed with cariprazine due to its pharmacokinetic and pharmacodynamic properties.