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Updated: Feb 1, 2026

Human Liver Microphysiological System for Assessing Drug-Induced Liver Toxicity In Vitro
Published on: January 31, 2022
SEQUENTIAL CHANGES IN HYDROXYCHLOROQUINE RETINOPATHY UP TO 20 YEARS AFTER STOPPING THE DRUG: Implications for Mild
Brandon H Pham1, Michael F Marmor2
1Stanford University School of Medicine, Stanford, California.
Purpose:
To characterize the stability or progression of different stages of hydroxychloroquine (HCQ) retinopathy up to 20 years after stopping the drug.
Methods:
We reviewed findings from 13 patients with initial HCQ retinopathy classified as early (patchy photoreceptor damage), moderate (ring of photoreceptor thinning or scotoma), or severe (retinal pigment epithelial [RPE] damage). Patients had been off HCQ for as many as 14 years at initial examination and were subsequently followed for 5 years to 8 years with repeated fundus autofluorescence and spectral domain optical coherence tomography.
Results:
Early and moderate cases stabilized in fundus autofluorescence appearance, foveal thickness, ellipsoid zone line length, and visual acuity for up to 9 years after stopping HCQ. By contrast, severe cases demonstrated a continual loss of these parameters for up to 20 years off the drug. The presence of RPE damage at initial examination predicted progressive retinopathy over many years.
Conclusion:
The steady progression of severe HCQ retinopathy in eyes showing RPE damage after drug cessation suggests a metabolic insult that chronically destabilizes rather than destroys cellular function, with a clinical course resembling that of genetic dystrophies. Our findings stress the importance of early detection to minimize progression and visual loss.
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