Chloroquine is now uncommonly used in favor of its derivative hydroxychloroquine. In the United States, hydroxychloroquine is most often used for its anti-inflammatory effects in rheumatology and dermatology. Chloroquine diphosphate solubility How is hydroxychloroquine taken Plaquenil make nails brittle Although it is considered rare, retinal toxicity from the intake of Plaquenil can be irreversible even if the drug is discontinued 2, 3. What is Plaquenil Toxicity? The toxicity resulting from the intake of Plaquenil is due to its affinity for melanin-containing structures in the body. Background The American Academy of Ophthalmology recommendations on screening for chloroquine CQ and hydroxychloroquine HCQ retinopathy are revised in light of new information about the prevalence of toxicity, risk factors, fundus distribution, and effectiveness of screening tools. Although the drug has a relatively safe systemic profile, its use is associated with an increased incidence of macular toxicity––particularly if an individual has been on Plaquenil therapy for many years. 1,2 Specifically, a 2010 study indicated that the overall risk of Plaquenil macular toxicity increases by about 2% for every 10 to 15. While early toxicity may be asymtomatic, patients with more advanced stage of toxicity may complain of color vision changes or paracentral scotomas. Its toxic effects on the retina are seen in the macula. Rates of plaquenil toxicity Multimodal Imaging in Plaquenil Toxicity, Recommendations on Screening for Chloroquine and. Plaquenil sideceffects Factors for toxicity related to hydroxychloroquine use. BACKGROUND 1 Hydroxychloroquine HCQ, brand name Plaquenil is commonly used for the long-term 2 management of a variety of chronic rheumatic diseases including systemic lupus erythematosus 3 and rheumatoid arthritis. A range of potential toxicities related to HCQ use have been reported AMERICAN COLLEGE OF RHEUMATOLOGY. Is Damage Still Occurring? - Review of Optometry. Rates and Predictors of Hydroxychloroquine Retinal.. Several risk factors may increase the likelihood of retinal toxicity from Plaquenil such as, age of greater than 60 years, daily dose more than 6.5 mg/kg; use of the drug more than 5 years, obesity, preexisting retinal disease and, renal or liver failure. Jan 05, 2020 Risk for toxicity is least with less than 6.5 mg/kg/day for hydroxychloroquine and 3 mg/kg/day for chloroquine. Patients are at low risk during the first 5 years of treatment. Cumulative use in excess of 250 grams increases the risk for toxic retinopathy. Other risk factors include obesity, kidney or liver disease, older age. Pharmacokinetics Following a single 200 mg oral dose of Plaquenil to healthy male volunteers, the mean peak blood concentration of hydroxychloroquine was 129.6 ng/mL, reached in 3.26 hours with a half-life of 537 hours 22.4 days. In the same study, the plasma peak concentration was 50.3 ng/mL reached in 3.74 hours with a half-life of 2963 hours 123.5 days.