| Item |
Information |
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Drug Groups
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approved |
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Description
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One of the folic acid antagonists that is used as an antimalarial or with a sulfonamide to treat toxoplasmosis. [PubChem] |
| Indication |
For the treatment of toxoplasmosis and acute malaria; For the prevention of malaria in areas non-resistant to pyrimethamine |
| Pharmacology |
Pyrimethamine is an antiparasitic compound commonly used as an adjunct in the treatment of uncomplicated, chloroquine resistant, P. falciparum malaria. Pyrimethamine is a folic acid antagonist and the rationale for its therapeutic action is based on the differential requirement between host and parasite for nucleic acid precursors involved in growth. This activity is highly selective against plasmodia and Toxoplasma gondii. Pyrimethamine possesses blood schizonticidal and some tissue schizonticidal activity against malaria parasites of humans. However, the 4-amino-quinoline compounds are more effective against the erythrocytic schizonts. It does not destroy gametocytes, but arrests sporogony in the mosquito. The action of pyrimethamine against Toxoplasma gondii is greatly enhanced when used in conjunction with sulfonamides. |
| Affected Organisms |
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| Biotransformation |
Hepatic |
| Absorption |
Well absorbed with peak levels occurring between 2 to 6 hours following administration |
| Half Life |
96 hours |
| Protein Binding |
87% |
| References |
| • |
Gatton ML, Martin LB, Cheng Q: Evolution of resistance to sulfadoxine-pyrimethamine in Plasmodium falciparum. Antimicrob Agents Chemother. 2004 Jun;48(6):2116-23.
[Pubmed]
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Sirichaiwat C, Intaraudom C, Kamchonwongpaisan S, Vanichtanankul J, Thebtaranonth Y, Yuthavong Y: Target guided synthesis of 5-benzyl-2,4-diamonopyrimidines: their antimalarial activities and binding affinities to wild type and mutant dihydrofolate reductases from Plasmodium falciparum. J Med Chem. 2004 Jan 15;47(2):345-54.
[Pubmed]
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| External Links |
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