Proguanil daily or chlorproguanil twice weekly are efficacious against falciparum malaria in a holoendemic area of Tanzania.

The prophylactic efficacy of proguanil 100 mg (Paludrine) daily was compared to that of chlorproguanil 20 mg (Lapudrine) twice weekly in school children from Nyamisathi village, in a coastal area of Tanzania, 160 km south of Dar es Salaam. A total of 80 children were randomly allocated to three groups after radical treatment with a curative dose of mefloquine (Lariam). Seventy-six children were then followed up with daily prophylaxis and/or placebo for 13 weeks. All children in the group taking placebo prophylaxis were reinfected within 10 weeks whereas no parasites were detected in the children taking proguanil or chlorproguanil for prophylaxis. We conclude that both regimens were efficacious and that chlorproguanil represents an important alternative for chemoprophylaxis if taken at least twice weekly instead of the recommended once weekly regimen.