Tablet, Oral, as phosphate: Generic: 250 mg [equivalent to chloroquine base 150 mg], 500 mg [equivalent to chloroquine base 300 mg] Binds to and inhibits DNA and RNA polymerase; interferes with metabolism and hemoglobin utilization by parasites; inhibits prostaglandin effects; chloroquine concentrates within parasite acid vesicles and raises internal p H resulting in inhibition of parasite growth; may involve aggregates of ferriprotoporphyrin IX acting as chloroquine receptors causing membrane damage; may also interfere with nucleoprotein synthesis Rapid and almost complete Widely in body tissues including eyes, heart, kidneys, liver, leukocytes, and lungs where retention is prolonged Partially hepatic to main metabolite, desethylchloroquine Urine (~70%; ~35% as unchanged drug); acidification of urine increases elimination; small amounts of drug may be present in urine months following discontinuation of therapy Serum: Oral: Within 1-2 hours 3 to 5 days ~55% Malaria: Treatment of uncomplicated malaria due to susceptible strains of Plasmodium vivax, Plasmodium malariae, Plasmodium ovale, and Plasmodium falciparum; prophylaxis of malaria (in geographic areas where chloroquine resistance is not present). Limitations of use: Chloroquine does not prevent relapses in patients with vivax or ovale malaria (not effective against exoerythrocytic forms). Extraintestinal amebiasis: Treatment of extraintestinal amebiasis. Data from a prospective, randomized, controlled, double-blind clinical trial supports the use of chloroquine in the treatment of discoid lupus erythematosus . Chloroquine dengue Drug treatment of chloroquine resistant malaria Metabolism Chloroquine undergoes metabolism by hepatic mechanisms. The main active metabolite is desethylchloroquine. Plasma half-life of desethylchloroquine is similar to chloroquine. The pharmacokinetics of chloroquine and its main metabolite desethylchloroquine have been carried out in volunteers with and without chloroquine‐induced pruritus. It was shown that the volunteers with pruritus tended to metabolize chloroquine slower than the volunteers without pruritus because the metabolic ratio was lower in the volunteers with pruritus than that in the volunteers without pruritus. Hydroxychloroquine HCQ and chloroquine CQ are well absorbed 0.7-0.8 bioavailability when given orally. Severe malnutrition such as kwashiorkor effects absorption but diahrrea does not. Both HCQ and CQ have prolonged half-lives, between 40 and 50 days, and low blood clearance e.g. hydroxychloroquine's blood clearance is 96 ml/min. Hypersensitivity to chloroquine, 4-aminoquinoline compounds, or any component of the formulation; the presence of retinal or visual field changes of any etiology (when used for indications other than acute malaria) Note: Chloroquine is currently under investigation for use in the treatment of COVID-19. Do not use for the treatment of complicated malaria (high-grade parasitemia and/or complications [eg, cerebral malaria, acute renal failure]) or for malaria prophylaxis in areas where chloroquine resistance occurs (resistance to chloroquine is widespread in P. Additional data may be necessary to further define the role of chloroquine in the treatment of this condition. Clinical pharmacokinetics and metabolism of chloroquine Pharmacokinetics and Metabolism of the Antimalarial., The disposition of chloroquine and its main metabolite. Synthesis of chloroquinePlaquenil lupus en espanol Ducharme J, Farinotti R Clinical pharmacokinetics and metabolism of chloroquine. Focus on recent advancements. Clin Pharmacokinet. 1996 Oct;314257-74. doi 10.2165/00003088-199631040-00003. Reaction Chloroquine to 1 product - DrugBank. Pharmacokinetics of hydroxychloroquine and chloroquine during.. Hydroxychloroquine - Wikipedia. The cytochrome P450 enzymes CYP2D6 17, 19 and CYP2C8 are known to participate in the metabolism of the primaquine and chloroquine, respectively. Two SNPs G416Ars11572080 and A805T rs11572103 were genotyped in the CYP2C8 gene. Excretion of Chloroquine is quite slow,but is increased by acidification of the urine. Chloroquine is deposited in the tissues in considerable amounts. In animals, from 200 to 700 times the plasma concentration may be found in the liver,spleen, kidney, and lung; leukocytes also concentrate the drug. There is differential binding and metabolism of the R and S stereoisomers. Both drugs bind strongly to pigmented tissues but also bind to mononuclear cells, muscles, etc. Clinical Pharmacokinetics of Antimalerial Drugs. Pharmacokinetics of chloroquine saliva and plasma levels relationship. Eur J Drug Metab Pharmacokin 1986; 11.