Hydroxychloroquine sulfate (Plaquenil; Sanofi-Aventis, Bridgewater, New Jersey) is an antimalarial agent, which is sometimes used for the treatment of certain autoimmune disorders. Its use has been associated with ocular side effects; the most concerning is toxic maculopathy.
A 71-year-old arthritic white woman requested a second opinion regarding retinal Plaquenil toxicity. The patients history was significant for seronegative rheumatoid arthritis diagnosed 6 years prior. She had taken Plaquenil 400 mg a day for about 5 years but had discontinued the drug 6 months before when bilateral central scotomas were first noted. At the consultation visit, her visual acuities were 20/20 in both eyes. SITA-Standard 10-2 disclosed a dense scotoma with 4 degrees of central sparing in each eye. Fundus examination found retinal pigment epithelium changes bilaterally; no "bulls eye" retinopathy was observed.
Withdrawal of the medication is the only effective treatment for Plaquenil toxicity and, even then, the toxic effects may progress because of the slow clearance of the drug. Though controversy exists regarding screening recommendations, a baseline ophthalmic examination should be performed on all patients before initiating Plaquenil. If a patient is considered low risk, examinations can be scheduled annually. For high-risk patients, 6-month progress visits are strongly recommended.