Chloroquine, a front-line drug in the treatment of malaria, has developed widespread
resistance, especially to the Plasmodium falciparum strains. Ciprofloxacin is a second-
generation quinolone used as a broad-spectrum fluoroquinolone antibacterial agent. The
possibility of using ciprofloxacin as an antimalarial, especially in chloroquine-resistant
strains, is very promising. They concluded from in vitro studies however that the anti-malarial
effect occur at high dose level of ciprofloxacin to achieve the required serum concentrations …

… The serum concentration of ciprofloxacin in humans was determined when ciprofloxacin was
given either alone or in combination with chloroquine. Five healthy male volunteers aged
(19–31) years, who were not taking any of the prescribed medications and who had no
sensitivity to either ciprofloxacin or chloroquine, each received 500 mg of ciprofloxacin orally
with 250 ml of water. After a two week-wash out period, 500 mg of ciprofloxacin plus 600 mg of
chloroquine was administered orally with 250 ml of water after informed consent. Blood samples …