INCREASED ANTIMALARIAL ACTIVITY OF AZITHROMYCIN DURING PROLONGED EXPOSURE OF PLASMODIUM-FALCIPARUM IN-VITRO

The minimum inhibitory concentration, MTC, of azithromycin was determi ned for 2 isolates of Plasmodium falciparum at 48 and 96 h. The MIC at 48 h for the K1 and FC isolates were 6.2 and 8.7 mu g/ml, respectivel y. At 96 h, the MIC decreased to 0.08 mu g/ml for the K1 isolate and 0 .04 mu g/ml for the FC isolate. The marked reduction in the MTC values between the first and second asexual erythrocytic cycles suggests tha t the drug acts slowly and that it may have to be used in combination with a faster acting drug.