Comparative Pharmacology
Head-to-head clinical analysis: CHLOROQUINE PHOSPHATE versus FANSIDAR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CHLOROQUINE PHOSPHATE versus FANSIDAR.
CHLOROQUINE PHOSPHATE vs FANSIDAR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Chloroquine is a 4-aminoquinoline that acts as a blood schizonticide. It inhibits heme polymerase in malaria parasites, preventing the conversion of toxic heme to hemozoin, leading to accumulation of toxic heme and parasite death. It also has anti-inflammatory and immunomodulatory effects via inhibition of toll-like receptors and cytokine production.
Fansidar combines sulfadoxine, a sulfonamide dihydrofolate reductase inhibitor, and pyrimethamine, a dihydrofolate reductase inhibitor, synergistically inhibiting folate synthesis in Plasmodium species, leading to nucleic acid synthesis inhibition and parasite death.
600 mg base (1 g phosphate) orally once daily for 2 days, then 300 mg base (500 mg phosphate) orally once daily for 3 days for malaria. For extraintestinal amebiasis: 600 mg base (1 g phosphate) orally once daily for 2 days, then 300 mg base (500 mg phosphate) orally once daily for 2-3 weeks.
For acute uncomplicated malaria: 3 tablets (25 mg pyrimethamine + 500 mg sulfadoxine per tablet) orally as a single dose on Day 0 and Day 1 (total 6 tablets); alternatively, 3 tablets as a single dose. For severe malaria: 3 tablets orally as a single dose, repeated at weekly intervals if necessary.
None Documented
None Documented
Terminal elimination half-life: 30-60 days (range 20-100 days); prolonged due to extensive tissue distribution and slow release from lysosomes.
Sulfadoxine: 100-200 hours; pyrimethamine: 80-100 hours; clinical context: unusual for antimalarials, allows single-dose therapy for uncomplicated P. falciparum
Renal: 50-70% as unchanged drug; hepatic/biliary: 20-30% as metabolites; fecal: up to 20%.
Renal: sulfadoxine 80% (unchanged), pyrimethamine 20-40% (unchanged); fecal: sulfadoxine <5%, pyrimethamine <5%
Category C
Category C
Antimalarial
Antimalarial