To the Editor: Quetiapine is a novel antipsychotic that has been associated with cataract formation in beagle dogs at high doses (1). The manufacturer recommends eye examinations to detect cataracts at baseline and at 6-month intervals in patients treated with quetiapine (1). To our knowledge, no reports of cataract formation in humans during quetiapine use have been published. We report on an inpatient who developed cataracts during quetiapine therapy.
Mr. A was a 44-year-old Latin American man with a 20-year history of schizophrenia and minimal response to fluphenazine, haloperidol, thioridazine, chlorpromazine, loxapine, and olanzapine. Clozapine treatment had resulted in agranulocytosis, necessitating discontinuation. Partial response had been achieved with risperidone, up to 10 mg/day; however, hostility and anxiety had persisted. Marked improvement in mood with decreased anxiety and hostility had been noted after the addition of quetiapine to risperidone therapy. The results of eye examinations at baseline, 6 months, and 12 months were unremarkable. Fifteen months after the addition of quetiapine, an optometry examination revealed lenticular changes in the left eye and grade I cortical spoking in the interior aspect of the lens (2). Quetiapine was tapered off over 9 days, and an eye examination conducted 1 month later showed no progression of cataract formation.
Soon after he stopped taking quetiapine, Mr. A became more anxious and had less behavioral control, requiring more use of anxiolytics. He and the treatment team evaluated the risks versus the benefits and decided that the combination of quetiapine and risperidone had provided the best response. Quetiapine was reintroduced at 700 mg/day, resulting in decreased hostility and anxiety and only occasional irritability. An eye examination then revealed water vacuoles in both lenses, suggesting cataract formation (3). Despite these lenticular changes, therapy with quetiapine, 700 mg/day, and risperidone, up to 10 mg/day, was maintained, which continued to control Mr. A’s symptoms. A later eye examination revealed no changes in the previous findings.
In a recent poster presentation, Nasrallah et al. (1999) reported lens opacities in 15 patients taking quetiapine. The majority of these patients had risk factors for cataracts, including heavy smoking, diabetes, hypertension, and advanced age. Four of the patients had not had a baseline eye examination, and four had a history of cataracts before taking quetiapine. The authors concluded that these findings did not demonstrate a strong association between the development of lens opacities with quetiapine therapy.
Although the possibility of coincidence cannot be excluded, our patient had a normal baseline eye examination and no history of cataracts before quetiapine treatment, and his only known risk factor for cataract formation was cigarette smoking. A MEDLINE search of articles on the patient’s other medications revealed no association with cataracts.