Quinine has been used worldwide for hundreds of years in the treatment of malaria. Thorough searches of the published literature identified over 1300 references to the treatment of malaria with quinine, and from these, 21 randomized, active-controlled studies were identified which evaluated oral quinine monotherapy or combination therapy for treatment of uncomplicated P. falciparum malaria. Over 2900 patients from malaria-endemic areas were enrolled in these studies, and more than 1400 patients received oral quinine. The following conclusions were drawn from review of these studies:
In areas where multi-drug resistance of P. falciparum is increasing, such as Southeast Asia, cure rates with 7 days of oral quinine monotherapy were at least 80%, while cure rates for 7-days of oral quinine combined with an antimicrobial agent (tetracycline or clindamycin) were greater than 90%. In areas where multi-drug resistance of the parasite was not as widespread, cure rates with 7 days of quinine monotherapy ranged from 86 to 100%. Cure was defined as initial clearing of parasitemia within 7 days without recrudescence by day 28 after treatment initiation. P. falciparum malaria that is clinically resistant to quinine has been reported in some areas of South America, Southeast Asia, and Bangladesh, and quinine may not be as effective in those areas.
Completion of a 7 day oral quinine treatment regimen may be limited by drug intolerance, and shorter courses (3 days) of quinine combination therapy have been used. However, the published data from randomized, controlled clinical trials for shorter regimens of oral quinine in conjunction with tetracycline, doxycycline, or clindamycin for treatment of uncomplicated P. falciparum malaria is limited, and these shorter course combination regimens may not be as effective as the longer regimens.