.svg | width = 240px | CAS_number = 118-42-3 | ATC_prefix = P01 | ATC_suffix = BA02 | PubChem = 3652 | DrugBank = | C = 18 |H = 26 |Cl = 1 |N = 3 |O = 1 | molecular_weight = 335.872 g/mol | bioavailability = | protein_bound = | metabolism = | elimination_half-life = 1-2 months | excretion = Renal | pregnancy_category = D (Au), C (U.S.)| legal_status = POM (UK), ℞-only (U.S.)| routes_of_administration = Oral}} Hydroxychloroquine is an antimalarial drug, sold under the trade name Plaquenil®, also used to reduce inflammation and in the treatment of arthritis (see Disease-modifying antirheumatic drugs) and lupus.