Successful treatment of intractable visual hallucinations with 5-HT 2A antagonist ketanserin.

Hallucinations, visual, auditory or in another sensory modality, often respond well to treatment in patients with schizophrenia. Some, however, do not and can be very chronic and debilitating. We present a patient with schizophrenia with intractable hallucinations despite state of the art care, including high-dose clozapine and transcranial magnetic stimulation. Based on the possible role of the 5-HT2A receptor in hallucinations, we treated her with the antihypertensive drug ketanserin, a 5-HT2A receptor antagonist.This significantly reduced her visual but not her auditory hallucinations, suggesting a possible role of the 5HT2A receptor in the pathophysiology of specifically visual hallucinations. This is the first time ketanserin has been described to successfully reduce visual hallucinations in a patient with schizophrenia.