Hydroxychloroquine and chloroquine retinopathy: screening for drug toxicity.

To report hydroxychloroquine and chloroquine retinopathy and consider screening for drug toxicity.Retrospective observational case series.Review of clinical records, visual fields, fundus photographs, and fluorescein angiography of six patients from a retina referral practice.All cases arose because of failure by physicians to avoid dosing above published safe levels. Five cases developed despite accepted ophthalmologic patterns of screening for toxicity. All cases developed parafoveal retinal pigment epithelial atrophic changes and paracentral scotomas to threshold visual field testing.New cases of hydroxychloroquine and chloroquine toxicity continue to develop in a screening environment. Increased ophthalmologic attention to dosing, awareness of location and nature of early visual field defects, and traditional attention to presence or absence of maculopathy can reduce the incidence of this avoidable condition.