Although not all of these side effects may occur, if they do occur they may need medical attention. Check with your doctor immediately if any of the following side effects occur while taking chloroquine: Incidence not known Some side effects of chloroquine may occur that usually do not need medical attention. Drug interaction chloroquine and ibuprofen Hydroxychloroquine sulfate 200 tabs Hydroxychloroquine sulfate classification The actual incidence of retinal toxicity from hydroxychloroquine is difficult to pin down because there is usually a long time between being started on the drug and the start of any identifiable retinal toxicity. The overall rate of probable retinal toxicity is in the range of 1 of every 200 people treated. Interactions Chloroquine toxicity may be increased by all drugs with quinidine-like effects. Combination with hepatotoxic or dermatitis-causing medication should be avoided, as well as with heparin risk of hemorrhage and penicillamine. Eye Keratopathy and retinopathy may occur when large doses of chloroquine are used for long periods. Hydroxychloroquine sulfate HCQ, Plaquenil is an analogue of chloroquine CQ, an antimalarial agent, used for the treatment of systemic lupus erythematosus, rheumatoid arthritis and other autoimmune disorders. Its use has been associated with severe retinal toxicity, requiring a discontinuation of therapy. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. These side effects may go away during treatment as your body adjusts to the medicine. Chloroquine eye toxicity Hydroxychloroquine And Chloroquine Screening 2016 AAO., Chloroquine C18H26ClN3 - PubChem Plaquenil and sarafem interactionsPlaquenil emotional side effectsPlaquenil dosing instructionsIs hydroxychloroquine an immune modulator Chloroquine and hydroxychloroquine can cause toxic retinopathy due to their binding of melanin in the retinal pigmented epithelium RPE as well as direct toxicity to retinal ganglion cells. Early findings include mottling of the RPE and blunted foveal reflex. As the retinopathy progresses, a bull's-eye maculopathy develops, as seen in these photos. Bull's-eye maculopathy due to hydroxychloroquine toxicity. Retinal toxicity associated with chronic exposure to.. Chloroquine - FDA prescribing information, side effects.. Chloroquine and hydroxychloroquine both belong to the quinolone family and share similar clinical indications and side effects, including retinal toxicity. Chloroquine-induced retinal toxicity was first described in 1959 and the retinal toxic effects of hydroxychloroquine were later described in 1967 3, 4. In 1959, Hobbs established a definite link between long-term use of chloroquine and subsequent development of retinal pathology. In 1962, J Lawton Smith coined the term bull's eye maculopathy, regarded as the classic finding of macular toxicity. Many reports on chloroquine retinopathy exist. The usefulness of hypokalemia as an indicator in the evaluation of chloroquine toxicity was studied in a retrospective series of 191 acute chloroquine poisonings. Results indicated that the risk of severe poisoning and death are proportional to the degree of hypokalemia.