Atovaquone (Mepron) is a medication used to treat or prevent Pneumocystis carinii pneumonia. It is also used to treat or prevent toxoplasmosis. The medication has antiparasitic and therapeutic effects. Atovaquone is a hydroxy-1,4-naphtoquinone, an analog of ubiquinone, with antipneumocystic activity. Trimotheoprim-sulfamethoxazole (TMP-SMX, Bactrim) is generally considered first line therapy for PCP (Pneumocystis carinii pneumonia) or toxoplasmosis. However, atovaquone may be used in patients who cannot tolerate, or are allergic to, TMP-SMX. more...
In addition, atovaquone has the advantage of not causing myelosuppression, which is an important issue in patients who have undergone bone marrow transplantation. Note: according to this source as of October 18, 2001 atovaquone has not been approved for treatment (or prophylaxis) of severe PCP.
Atovaquone is also used in the chemical phophylaxis and treatment of malaria.
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