Effectiveness of amodiaquine, sulfadoxine-pyrimethamine, and combinations of these drugs for treating chloroquine-resistant falciparum malaria in Hainan Island, China.

The study was carried out in 1985-86 in Hainan Island where Plasmodium falciparum is resistant to chloroquine. Fifty cases of falciparum malaria were treated with 1800 mg amodiaquine for 3 days: the cure rate was 65.3%, and the mean time to clear fever and asexual parasitaemia was 30.7 and 60.3 hours, respectively; 34.7% of cases showed RI or RII recrudescence, and one patient's temperature did not come down to normal within 7 days.Twenty-one cases were treated with sulfadoxine-pyrimethamine (1500 mg and 75 mg, respectively): 19 were cured, I showed RI and another had an S or RI response; the mean time for fever control was 56.1 hours.Fifty cases were treated with amodiaquine plus sulfadoxine and 49 received amodiaquine plus sulfadoxine-pyrimethamine: the cure rate was 97.9% and 100%, respectively; the mean time for fever clearance was 25.0 and 25.7 hours and for parasite clearance 57.1 and 52.8 hours, respectively. These drug combinations gave much better results for cure and for symptom control than amodiaquine or sulfadoxine-pyrimethamine alone, and may be considered for treatment of chloroquine-resistant falciparum malaria.