Hydroxychloroquine Retinopathy. Retinopathy has been reported to be dose-related. Retinopathy is more commonly associated with chloroquine than with hydroxychloroquine and can result in patients developing circular defects known as bulls eye maculopathy and diametric.
Hydroxychloroquine and Chloroquine Retinopathy. Hydroxychloroquine and chloroquine are weak bases and have a characteristic deep volume of distribution and a half-life of around 50 days. Following the publication of the RCOphth recommendations for monitoring in hydroxychloroquine and chloroquine users in 2018 new published evidence prompted a review of the guideline.
Hydroxychloroquine is used to treat the symptoms of rheumatoid arthritis and systemic lupus erythematosus and to prevent and treat malaria.
Chloroquine and hydroxychloroquine are moderate inhibitors of cytochrome P450 CYP 2D6 and these drugs are also P-glycoprotein P-gp inhibitors. People who take hydroxychloroquine for more than five years should get regular eye exams. Patients are at low risk during the first 5 years of treatment. Retinopathy has been reported to be dose-related.