Aripiprazole is a dopamine partial agonist with a low risk of movement disorder and metabolic adverse effects.

We identified 228 patients consecutively prescribed aripiprazole in our unit and established outcome (continuation with treatment) six months after initiation.

The study cohort consisted of subjects of mean age 36.2 years (17-86) of whom 53.1% were male. Two thirds had a diagnosis of schizophrenia. Overall, 112 (49%) patients completed 6 months' treatment. Reasons for discontinuation were adverse events (n = 61, 53% of those who stopped), lack of effectiveness (n = 45, 39%) and a variety of unconnected reasons (n = 10, 9%). The majority of discontinuations (n = 76, 66%) occurred in the first 60 days of treatment, largely because of adverse effects. Most common adverse events reported were anxiety/agitation (n = 57, 25% of total cohort), insomnia (n = 43, 19%) and movement disorder (n = 24, 11%).

Treatment discontinuation was more likely for in-patients than out-patients (61% vs 42%, p = 0.005) and in those previously prescribed clozapine (p = 0.01). Modal initiation dose was 15mg for patients starting in the first year of the study and 10mg for those starting later. Initiation dose was not associated with outcome.

Aripiprazole showed a degree of effectiveness similar to that shown by other antipsychotics. Early-appearing, trivial adverse events are a major factor in treatment discontinuation. Outcome is best in out-patients and those not formerly treated with clozapine.