Ophthalmologic considerations and testing in patients receiving long-term antimalarial therapy

Area of Science:

• Ophthalmology
• Pharmacology
• Toxicology

Background:

• The precise mechanisms of retinal toxicity from antimalarial drugs are not fully elucidated.
• Hydroxychloroquine (HCQ) is associated with a lower risk of retinopathy compared to chloroquine (CQ).
• The risk of developing retinopathy increases with the duration of antimalarial therapy.

Purpose of the Study:

• To evaluate the benefit/risk ratio of hydroxychloroquine compared to chloroquine for retinal toxicity.
• To identify optimal monitoring strategies for detecting antimalarial-induced retinopathy.

Main Methods:

• Comparative analysis of retinal toxicity risk between HCQ and CQ.
• Review of diagnostic methods for retinopathy, including ophthalmoscopy, fundus photography, visual field testing, and perimetry.
• Guidelines for baseline and follow-up ophthalmologic examinations.

Main Results:

• The benefit/risk ratio for HCQ is comparable or superior to CQ.
• At recommended dosages (HCQ 400 mg/day, CQ 250 mg/day), the benefit/risk ratio is medically and ophthalmologically acceptable.
• Ophthalmoscopy, macular examination, visual field testing, and automated perimetry are key diagnostic tools.

Conclusions:

• Hydroxychloroquine offers a favorable safety profile regarding retinal toxicity compared to chloroquine.
• Adherence to recommended dosages and regular, systematic ophthalmologic monitoring are essential for patient safety.
• Early detection and referral are critical for managing potential ocular abnormalities, even in asymptomatic patients.