PIC QUESTION OF THE WEEK: 5/01/06 Q: What is the best preventive regimen against malaria for a pregnant woman traveling to Kenya? A: Malaria develops in an estimated 300-500 million people per year and is responsible for approximately one million deaths annually, mainly in sub-Saharan Africa. Most fatalities are due to the species Plasmodium falciparum. Malaria is caused by a single-celled parasite, transmitted by mosquitoes, and characterized by recurring attacks of moderate to severe shaking chills, high fever, profuse sweating, and malaise. Malaria in pregnancy causes a significant rate of mortality for both the mother and unborn child. If at all possible, pregnant women should avoid travel to malarious areas. When travel is necessary, these women must utilize insecticide-treated nets (ITNs) and topical agents to prevent insect bites. One study concluded that regular application of DEET during the second and third trimesters of pregnancy did not result in harm to the fetus. In addition, chemoprophylaxis is highly recommended. Kenya has a high incidence of malaria, thus, a prophylactic drug regimen must be administered. This country, along with most others in sub-Saharan Africa and the Indian subcontinent harbor plasmodium species that are almost routinely resistant to chloroquine. In these cases, alternative regimens must be considered. Chloroquine appears to be safe during all trimesters of pregnancy (although listed as FDA Category C). Medications carrying an FDA labeled indication for prophylaxis of malaria are: atovaquone/proguanil (Malarone; Category C), mefloquine (Lariam; Category C), and doxycycline. Primaquine has also been used, but is not FDA-labeled for this indication. Both doxycycline and primaquine are contraindicated for use during pregnancy. The safety of atovaquone/proguanil in pregnant women has not been adequately evaluated. In one study of 24 women using the drug in the second and third trimester, outcomes were normal. Proguanil, a component of the combination, has been used extensively without evidence of teratogenic potential. Mefloquine is not labeled for administration during pregnancy and its prophylactic use has been associated with increased rates of spontaneous abortion. The drug has, however, been reported to be safe during the second and third trimesters of pregnancy and some authors feel it may be used during the first trimester as well. The CDC currently recommends that pregnant women traveling to chloroquine-resistant areas such as Kenya receive mefloquine for malaria prophylaxis. Individual cases can be referred to the CDC Malaria Hotline at 770-488-7788. References: • • •
Centers for Disease Control and Prevention. Preventing malaria in the pregnant woman. www.cdc.gov/travel/mal_preg_hc.htm (accessed 2006 April 26) Anonymous. Advice for travelers. Treatment Guidelines Med Let 2006; 45;25-34 Baird JK. Effectiveness of antimalarial drugs. N Engl J Med 2005;352:1565-77.
Alyssa M. Stein, Pharmacy Clerkship Student The PIC Question of the Week is a publication of the Pharmaceutical Information Center, Mylan School of Pharmacy, Duquesne University, Pittsburgh, PA 15282