Q: I recently started taking Plaquenil for rheumatoid arthritis and was asked to see an eye doctor for a complete exam and special testing. Why is this necessary?
A: Plaquenil, hydroxychloroquine (HCQ), is in a class of medications first used to prevent and treat malaria. Today, Plaquenil is a proven and widely used medication in the treatment of rheumatoid arthritis, lupus, and other inflammatory conditions and autoimmune diseases. When taking any systemic medication such as Plaquenil, there are possible risks and side effects related to the eyes. Although rare, Plaquenil usage can cause retinal toxicity that could lead to irreversible vision damage or vision loss.
Patients starting treatment with Plaquenil should have a baseline eye examination within the first year of taking this medication and then regular screenings thereafter; every six months or yearly as advised by your eye doctor. This exam should involve several baseline measurements and assessments that can be compared over time to monitor any changes to your vision including refraction, visual acuity, dilated fundus exam, and a visual field test and/or an OCT, ocular coherence tomography, which is a photograph of the macula.
In early toxicity from Plaquenil, there are no visible signs to the patient but there are changes that can be detected by the visual field and OCT testing. Generally, if there is Plaquenil toxicity present, it is bilateral (both eyes) and symmetric. Risk factors that may increase the likelihood of Plaquenil toxicity include age over 60, daily dose of more than 400 mg, use of Plaquenil for more than 5 years, obesity, pre-existing retinal disease, and renal or liver failure. When the maximum daily dosage recommendations for Plaquenil are followed, the likelihood of toxicity is very small.
As a patient taking Plaquenil, make sure to discuss the risks and benefits of this medication with both the prescribing physician and your eye doctor. You should also understand the benefits and limitations of visual screenings. Regular physical exams along with periodic comprehensive eye exams and testing are essential to monitor the health of your eyes while taking Plaquenil.