As optometrists, it is important that we are aware of the possible ocular complications that can occur from the use of high risk medications.
Patients starting chloroquine (CQ) or hydroxychloroquine (HCQ; i.e. Plaquenil) should have a baseline examination that serves as a reference point, as well as to rule out any preexisting maculopathies.
While most rheumatologists are now routinely prescribing their patients 400 mg of HCQ (or 250 mg CQ) daily for the management of conditions like systemic lupus erythematosus and rheumatoid arthritis, individuals of short stature often have their dosage determined off of their ideal body weight to avoid overdosing.
Annual screening should begin after 5 years of medication use unless the patient has any of the unusual risk factors described below.
Unusual risk factors that increase the risk of CQ or HCQ Retinopathy:1
- Total cumulative dose >460 g of CQ or > 1000 g of HCQ
- Daily Dose > 250 mg/day CQ or >400 mg/day HQC
- Age, kidney dysfunction, liver dysfunction, retinal disease or maculopathy
American Academy of Ophthalmology Recommended Screening:1
Complete ocular health examination including a dilated retinal assessment
- Concern: Preexisting retinal disease and bullseye maculopathy
10-2 visual field
- Concern: Paracentral scotomas with decreased foveal sensitivity
One (or more) of the following tests:
Spectral domain OCT of the Macular
- Concern: Parafoveal thinning of photoreceptor layers and/or loss of the inner-segment/outer-segment junction
- Concern: Decreased parafoveal waveform amplitudes
- Concern: Parafoveal hyperfluorescence
It's critical to educate your patients on the risk of toxicity and the importance of screening. If early changes and/or visual loss is detected, consult with your patient's prescribing doctor immediately, as they should discontinue the medication and consider alternative therapies.