Her rheumatologist instructed her to undergo a baseline ocular examination prior to initiating Plaquenil (hydroxychloroquine, Sanofi-Aventis) therapy. Toxic maculopathy associated with chloroquine use was first documented in the literature five decades ago.1 In the United States, Plaquenil––an analog to chloroquine––is used to treat a variety of conditions, including rheumatoid arthritis, lupus and several distinct inflammatory disorders. Although the incidence of macular toxicity is infrequent with Plaquenil use (at a dosage of 200mg or 400mg q.d.), its visual impact can be devastating. Chloroquine cq Chloroquine mechanism of resistance Chloroquine macrophages Hydroxychloroquine comes in an oral tablet. Adult dosing ranges from 200 mg or 400 mg per day 6.5mg/kg. In some cases, higher doses can be used. It is recommended one tablet twice daily if taking more than one tablet. It is recommended to be taken with food. Prophylaxis 400 mg 310 mg base PO weekly, starting 2 weeks before exposure and continued for 4 weeks after departure from area. With prolonged therapy, obtain CBCs periodically. 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. Initially, central visual acuity may be unaffected, but the patient may notice related paracentral scotomas that often interfere with reading. The associated classic retinal toxicity is described as a bull’s eye maculopathy (ring of depigmented retinal pigment epithelium that spares the foveal area). Hydroxychloroquine dosing guidelines Hydroxychloroquine Plaquenil dosing Are we following., Plaquenil hydroxychloroquine sulfate dosing, indications. Stopped my plaquenilSide effects of hydroxychloroquine plaquenil Both adults and children should take one dose of hydroxychloroquine per week starting at least 1 week. before traveling to the area where malaria transmission occurs. They should take one dose per week while there, and for 4 consecutive weeks after leaving. The weekly dosage for adults is 310mg base 400mg salt. Medicines for the Prevention of Malaria While Traveling.. Recommendations on Screening for Chloroquine and.. Hydroxychloroquine dosing guidelines have little impact in.. An audit of 100 patients seen at any of nine Canadian rheumatology clinics during early 2016 showed that 30% of patients were not on appropriate weight-based hydroxychloroquine dosages, and 13% of patients on the drug had not received a baseline retinal assessment during their first year. Guidelines recommend hydroxychloroquine as an alternative to chloroquine as a treatment option for acute malaria and for prophylaxis in pregnant women during all trimesters. Hydroxychloroquine may also be appropriate for pregnancies complicated by lupus. The guidelines were never intended to restrict the use of HCQ by rheumatologists, but rather to facilitate the prescription of HCQ by rheumatologists. He described the essentials of the guidelines, which recommend the maximum dose of HCQ should be ≤5.0 mg/kg of actual weight.