Department of Infectious Diseases, Mälarsjukhuset Eskilstuna and Karolinska Institute, Stockholm, Sweden.
A long tradition of successful malaria prophylaxis with chloroquine led to a dogma that drug prophylaxis should be given regardless of risk as soon as a traveler entered endemic areas. This prevailed also when resistance to chloroquine and adverse effects of alternatives became a problem. A cost/benefit analysis of the risk for malaria versus risk for adverse effects and cost of the recommended drug is not uniformly applied and drug prophylaxis is still advocated even when the risk for severe adverse effects greatly exceeds the risk for malaria, which is unethical.