Comparative Pharmacology
Head-to-head clinical analysis: ATOVAQUONE versus PYRIMETHAMINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ATOVAQUONE versus PYRIMETHAMINE.
ATOVAQUONE vs PYRIMETHAMINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Atovaquone is a hydroxynaphthoquinone that selectively inhibits mitochondrial electron transport chain complex III (cytochrome bc1 complex) in parasites, thereby disrupting pyrimidine synthesis and energy metabolism.
Pyrimethamine inhibits dihydrofolate reductase (DHFR) in the parasite, blocking the conversion of dihydrofolate to tetrahydrofolate, thereby inhibiting nucleic acid synthesis.
750 mg oral suspension twice daily for treatment of mild-to-moderate Pneumocystis jirovecii pneumonia; 1500 mg oral suspension once daily for prophylaxis.
For toxoplasmosis: 200 mg orally once, then 50-75 mg orally once daily for 4-6 weeks, plus sulfadiazine and folinic acid. For malaria prophylaxis: 25 mg orally once weekly.
None Documented
None Documented
Clinical Note
moderateAtovaquone + Indinavir
"The serum concentration of Indinavir can be decreased when it is combined with Atovaquone."
Clinical Note
moderatePyrimethamine + Fesoterodine
"The serum concentration of the active metabolites of Fesoterodine can be increased when Fesoterodine is used in combination with Pyrimethamine."
Clinical Note
moderateAtovaquone + Artemether
"The risk or severity of QTc prolongation can be increased when Atovaquone is combined with Artemether."
Clinical Note
moderateTerminal elimination half-life is approximately 2-3 days (67 hours) in adults, prolonged in renal or hepatic impairment.
Terminal elimination half-life is approximately 96 hours (range 80-123 hours) in adults with normal renal function; prolonged in renal impairment (up to 200 hours). This long half-life supports weekly dosing regimens.
Primarily fecal (>94%) as unchanged drug; renal excretion is minimal (<1%).
Primarily renal (approximately 30% unchanged and 20-30% as metabolites); additional biliary/fecal elimination (20-30% as metabolites). Total urinary excretion of parent drug and metabolites accounts for 60-80% of dose.
Category A/B
Category D/X
Antiprotozoal
Antimalarial / Antiprotozoal
Pyrimethamine + Artemether
"The risk or severity of QTc prolongation can be increased when Pyrimethamine is combined with Artemether."