Chloroquine in malaria. Isn't it time for revision of prophylaxis schedules?

Two antimalarial prophylactic regimens were compared in healthy subjects belonging to the flying personnel of Scandinavian Airlines System. Regimen I: 310 mg chloroquine (CQ) base was given once weekly, starting the week prior to departure to the endemic area, then weekly during presence there and for four weeks after return. Regimen II: a loading dose of 620 mg chloroquine base was given at the latest 48 h prior to departure to the endemic area, followed by 310 mg base weekly throughout the visit.