title: Efficacy of a loading dose of oral chloroquine in a 36-hour treatment schedule for uncomplicated plasmodium falciparum malaria.
abstract: The efficacy of a loading dose of 20 mg of chloroquine per kg of body weight per os given at intervals during the first day was evaluated in 27 patients in Madagascar with Plasmodium falciparum malaria. The conventional regimen of 25 mg/kg over 3 days (schedule 1) was thus compared with a regimen of 30 mg/kg over 2 days (schedule 2; one dose of 10 mg/kg followed by two doses of 5 mg/kg at 6-h intervals on the first day and two doses of 5 mg/kg at 12-h intervals on the second day) in terms of their clinical and parasitological efficacies, tolerance, and drug concentration-time curves. At 24 h schedule 2 gave higher chloroquine levels in blood, which induced a more rapid decrease in parasitemia. The time required for a 50% decrease in the initial parasitemia was shorter in patients on schedule 2 (14.3 +/- 1.6 h) than it was in patients on schedule 1 (35.5 +/- 5.4 h; P less than 0.01). Moreover, negative blood smears were obtained more rapidly with schedule 2 (50.8 +/- 3.7 h) than with schedule 1 (72 +/- 8.7 h). As predicted by the drug concentration-time curve, no high, potentially toxic peak drug concentration appeared and no adverse effects were observed with the loading dose regimen (schedule 2). These findings support the idea that a loading dose of 20 mg/kg given at intervals during the first 12 h is well tolerated and can be used to obtain a more rapid decrease in parasitemia and to shorten the treatment time of uncomplicated chloroquine-susceptible falciparum malaria in the field.
authors.affiliation: Hôpital Claude Bernard, Institut de Médecine et d'Epidémiologie Africaine, Institut National de la Santé et de la Recherche Médicale U13, Paris, France.
authors.forename: E
authors.initials: E
authors.lastname: Pussard
authors.forename: J P
authors.initials: JP
authors.lastname: Lepers
authors.forename: F
authors.initials: F
authors.lastname: Clavier
authors.forename: L
authors.initials: L
authors.lastname: Raharimalala
authors.forename: J
authors.initials: J
authors.lastname: Le Bras
authors.forename: M
authors.initials: M
authors.lastname: Frisk-Holmberg
authors.forename: Y
authors.initials: Y
authors.lastname: Bergqvist
authors.forename: F
authors.initials: F
authors.lastname: Verdier
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D002675:Child, Preschool; D002738:Chloroquine / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000494:pharmacology; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008288:Malaria / Q000188:drug therapy*; D008297:Male; D010963:Plasmodium falciparum / Q000187:drug effects*
chemical_list: D002738:Chloroquine