"Potential drug treatments are tested on paper, in laboratories and eventually in thousands of people. But every drug that goes through this cycle â€“ every drug that FDA approves â€“ carries some risk. One of the first lines of defense against "...
Pyrimethamine is well absorbed with peak levels occurring between 2 to 6 hours following administration. It is eliminated slowly and has a plasma half-life of approximately 96 hours. Pyrimethamine is 87% bound to human plasma proteins.
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. This was demonstrated by Eyles and Coleman1 in the treatment of experimental toxoplasmosis in the mouse. Jacobs et al2 demonstrated that combination of the 2 drugs effectively prevented the development of severe uveitis in most rabbits following the inoculation of the anterior chamber of the eye with toxoplasma.
1. Eyles DE, Coleman N. Synergistic effect of sulfadiazine and Daraprim against experimental toxoplasmosis in the mouse. Antibiot Chemother 1953;3:483-490.
2. Jacobs L, Melton ML, Kaufman HE. Treatment of experimental ocular toxoplasmosis. Arch Ophthalmol. 1964;71:111-118.
Last reviewed on RxList: 9/30/2015
This monograph has been modified to include the generic and brand name in many instances.
Additional Daraprim Information
Daraprim - User Reviews
Daraprim User Reviews
Now you can gain knowledge and insight about a drug treatment with Patient Discussions.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Find out what women really need.