Background Previous experience with unacceptable adverse effects with mefloquine as treatment for uncomplicated Plasmodium falciparum malaria prompted an evaluation of the effectiveness and side effects of atovaquone–proguanil (Malarone) in a hospital setting.

Methods Atovaquone–proguanil was given as standard treatment (1,000/400mgq.d. for 3 days) to 50 adults who had traveled in Africa and returned with uncomplicated Plasmodium falciparum malaria. Half of the treated patients were African and had lived outside Africa for varying periods of time; the other half were Danish-born persons without any previous immunity towards malaria.

Results All patients treated with Malarone were cured without complications. The mean fever clearance times differed among the groups and according to various degrees of prior exposure to malaria and ranged from 1.3 to 2.2 days. Adverse effects during treatment were mild, and were likely to be due to the malaria itself. Fourteen people who had acquired falciparum malaria in spite of taking proguanil–chloroquine prophylaxis were also cured uneventfully without recrudescence.

Conclusions Malarone appears to be an effective, safe and acceptable oral treatment for uncomplicated malaria.