Chloroquine and its congeners can cause two typical effects in the eye, a keratopathy and a specific retinopathy. Both of these effects are associated with the administration of the drug over longer periods of time. Chloroquine-induced keratopathy is limited to the corneal epithelium, where high concentrations of the drug are readily demonstrable. Slit lamp examination shows a series of punctate opacities scattered diffusely over the cornea; these are sometimes seen as lines just below the center of the cornea, while thicker yellow lines may be seen in the stroma.
