PEARLS No. 244, April 2010, written by Brian R McAvoy

Clinical question
What is the most effective and safest prophylactic anti-malarial for non-immune adults and children travelling to regions with Plasmodium falciparum resistance to chloroquine?  

Bottom line
Atovaquone-proguanil and doxycycline were well tolerated by most travellers, and they were less likely than mefloquine to cause neuropsychiatric adverse events. Chloroquine-proguanil caused more gastrointestinal adverse events than other chemoprophylaxis. In other respects, the common unwanted effects of currently available drugs were similar. There was no evidence from head-to-head comparisons to support primaquine use as primary prophylaxis for travellers. The choice of whether to prescribe atovaquoneproguanil or doxycycline (or exceptionally, mefloquine) should be made by health practitioners by taking into account additional factors such as cost, known contraindications to any of the drugs in question (eg, pregnancy, breastfeeding, age), known rare serious adverse events, previous use of the drugs, possible drug-drug interactions, ease of administration, travel itinerary and the additional protection that may be afforded by doxycycline against other infections, besides malaria.  

Caveat
The body of evidence was small, and the quality of evidence ranged from very low to moderate. Except for 2 trials, all the studies in this review were funded wholly or in part by pharmaceutical companies. As well as the 8 trials, there were also 22 published case reports of deaths, including five suicides, associated with mefloquine use at normal dosages. No other currently used drugs were reported as causing death at normal dosages.  

Context
Malaria infects 10,000 to 30,000 international travellers each year. It can be prevented through anti-mosquito measures and drug prophylaxis. However, anti-malarial drugs have adverse effects which are sometimes serious.  

Cochrane Systematic Review
Jacquerioz FA and Croft AM. Drugs for preventing malaria in travellers. Cochrane Reviews 2009, Issue 4. Article No. CD006491. DOI: 10.1002/14651858.CD006491.pub2. This review contains 8 studies involving 4240 participants.