Comparative Pharmacology
Head-to-head clinical analysis: PYRIMETHAMINE SULFADOXINE versus QUININE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PYRIMETHAMINE SULFADOXINE versus QUININE.
Pyrimethamine-Sulfadoxine vs Quinine
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Pyrimethamine inhibits dihydrofolate reductase, blocking tetrahydrofolate synthesis. Sulfadoxine inhibits dihydropteroate synthase, blocking folate synthesis. Sequential blockade of folate metabolism.
Quinine is a cinchona alkaloid that acts as a blood schizonticide against Plasmodium falciparum. It inhibits heme polymerase, leading to accumulation of toxic heme, and disrupts parasite membrane integrity. It also has mild analgesic and antipyretic properties.
Pyrimethamine 25 mg plus sulfadoxine 500 mg per tablet; typical adult dose for acute uncomplicated malaria is 3 tablets (pyrimethamine 75 mg, sulfadoxine 1500 mg) orally as a single dose. For toxoplasmosis in immunocompromised patients: loading dose pyrimethamine 200 mg orally once, then pyrimethamine 50-75 mg orally once daily plus sulfadoxine 1000-1500 mg orally once daily (dosing based on sulfadoxine component) for 4-6 weeks, then reduce to half.
Adults: 648 mg (2 capsules) orally every 8 hours for 7 days for uncomplicated chloroquine-resistant malaria, typically used in combination with other antimalarials.
None Documented
None Documented
Clinical Note
moderateQuinine + Gatifloxacin
"Quinine may increase the hypoglycemic activities of Gatifloxacin."
Clinical Note
moderateQuinine + Rosoxacin
"Quinine may increase the hypoglycemic activities of Rosoxacin."
Clinical Note
moderateQuinine + Levofloxacin
"Quinine may increase the hypoglycemic activities of Levofloxacin."
Clinical Note
moderateQuinine + Trovafloxacin
"Quinine may increase the hypoglycemic activities of Trovafloxacin."
Pyrimethamine: ~80-120 hours; Sulfadoxine: ~100-200 hours. Long half-lives allow single-dose therapy for malaria.
Terminal elimination half-life: 18 hours (range 8–21 h) in healthy adults; prolonged to 26–44 h in severe malaria or hepatic impairment.
Renal: ~60% unchanged sulfadoxine, ~5% unchanged pyrimethamine; fecal: ~10% pyrimethamine. Biliary excretion minimal.
Renal: ~20% unchanged; Hepatic metabolism (CYP3A4) to inactive metabolites, excreted in urine and feces. Total renal elimination of parent and metabolites ~80%.
Category C
Category C
Antimalarial
Antimalarial