Differential sensitivities to risperidone and olanzapine in a human immunodeficiency virus patient

Background: Neuroleptic sensitivity presents a considerable problem for the treatment of psychosis in the acquired immunodeficiency syndrome (AIDS) and human immunodeficiency virus (HIV)-positive patient population. As yet, there are few data on the response of these patients to newer atypical antipsychotic medications. Methods: We present the detailed medication history of a 33-year-old man with AIDS, who had a prior history of extrapyramidal symptoms (EPS) with both typical antipsychotics and risperidone, and was treated with olanzapine for major depression with psychotic features. Results: The patient developed akathisia in a dose-dependent manner at dosages between 10 and 15 mg daily of olanzapine, but no EPS. Akathisia responded to dose reduction and use of β-adrenergic blockade. Conclusions: The AIDS patient may exhibit sensitivity even to newer atypical antipsychotics. The lack of EPS and response to a β-blocker underscore the different mechanisms causing akathisia and EPS.