Clinical efficacy of mefloquine in children suffering from chloroquine-resistant Plasmodium falciparum malaria in Nigeria.

One hundred and thirteen children with symptomatic uncomplicated falciparum malaria were treated with either chloroquine 25 mg/kg body weight over 3 d (51 subjects) or mefloquine 25 mg/kg body weight single dose (62 subjects). The cure rate in the chloroquine group was 65% and in the mefloquine group 100%. 14 patients with chloroquine-resistant falciparum malaria (7 RI, 6 RII and one RIII) were successfully treated with mefloquine. The clearance times of parasitaemia and fever were 60 +/- 21.5 h and 24.7 +/- 10.1 h respectively in the chloroquine-sensitive group and 52.3 +/- 18.2 h and 24.5 +/- 23.7 h respectively in the mefloquine group. In the chloroquine-resistant group treated successfully with mefloquine, these clearance times were 44.0 +/- 8.9 and 24.0 h respectively. The only remarkable adverse reaction in the chloroquine group was pruritus which occurred in 7 subjects. Abdominal pain and diarrhoea (8 subjects) and dizziness (3 subjects) were the only important adverse reactions in the mefloquine group. It is concluded that, despite previous reports of primary reduced susceptibility to mefloquine in vitro of some West African isolates of Plasmodium falciparum, this drug may be useful in the treatment of both chloroquine-sensitive and chloroquine-resistant falciparum malaria in West Africa.