Self-reported adverse events associated with antimalarial chemoprophylaxis in peace corps volunteers

To determine adverse events associated with the use of antimalarial chemoprophylaxis in Peace Corps volunteers who have served in malaria-endemic countries 6 months or longer.

Survey of Peace Corps volunteers' adverse events associated with the use of antimalarial chemoprophylaxis between August 1, 2005 and July 31, 2006. Analyses were conducted in fall 2006.

Two thousand seven hundred and one surveys were received (43% response rate) from volunteers in malaria-endemic countries, with 1,731 (64%) in country for 6 months or longer (average 19 months). Nearly two thirds (62%) reported at least one adverse event. Those on mefloquine reported the most neuropsychologic adverse events; those on doxycycline reported the most gastrointestinal as well as skin and vaginal adverse events. Nearly one quarter of respondents (23%) changed their chemoprophylaxis regimen due to adverse events. Severe adverse events were reported by 9% of respondents, and 1% reported being hospitalized.

Adverse events were frequently reported among volunteers using antimalarial medications for more than 6 months, but very few were severe or required hospitalization. In light of the large number of adverse events, having multiple drug regimens available for the long-term traveler may be one method of maintaining adherence to antimalarial chemoprophylaxis.