From the Guidelines
Malaria prophylaxis should be taken seriously, and the most effective regimen for most travelers is atovaquone-proguanil (Malarone), taken daily starting 1-2 days before travel, throughout the stay, and for 7 days after leaving the malaria-endemic area, as it provides substantial protection against malaria infection. The adult dose is one tablet (250mg atovaquone/100mg proguanil) daily 1. Alternative options include doxycycline (100mg daily, starting 1-2 days before travel and continuing for 4 weeks after return), or mefloquine (250mg weekly, starting 2-3 weeks before travel and continuing for 4 weeks after return) 1. Chloroquine (500mg weekly) can be used in the few areas without chloroquine-resistant parasites, but its efficacy is limited in sub-Saharan Africa and low in South East Asia 1.
Key Considerations
- Compliance is essential, and most deaths are in those who do not comply fully with the recommended prophylaxis regimen 1.
- Travelers should understand that malaria can be treated effectively early in the course of the disease, but delay of appropriate therapy can have serious or even fatal consequences 1.
- Beyond medication, preventive measures include:
- Using insect repellent containing DEET
- Wearing long sleeves and pants especially during evening hours
- Sleeping under insecticide-treated bed nets
- Using air conditioning when available
- Pregnant women, children, and those with certain medical conditions require special consideration for prophylaxis regimens and should consult healthcare providers for personalized recommendations 1.
Chemoprophylactic Regimens
- Atovaquone-proguanil (Malarone) is the recommended regimen for most travelers, due to its high efficacy and relatively low risk of side effects 1.
- Doxycycline and mefloquine are alternative options, but may have more side effects and require longer durations of treatment 1.
- Chloroquine is only recommended for areas without chloroquine-resistant parasites, and its use should be carefully considered due to its limited efficacy in many regions 1.
From the FDA Drug Label
Prevention of Malaria: Atovaquone and proguanil hydrochloride was evaluated for prophylaxis of malaria in 5 clinical trials in malaria-endemic areas and in 3 active-controlled trials in non-immune travelers to malaria-endemic areas Malaria Prophylaxis in Adults Dosage: One 250 mg mefloquine hydrochloride tablet once weekly. The recommended prophylactic dose of mefloquine hydrochloride is approximately 5 mg/kg body weight once weekly.
The recommendations for Malaria prophylaxis are:
- Atovaquone and proguanil hydrochloride: The dosage is not explicitly stated for prophylaxis in the provided text, but it is mentioned that atovaquone and proguanil hydrochloride was evaluated for prophylaxis of malaria in several clinical trials.
- Mefloquine:
- Adults: One 250 mg mefloquine hydrochloride tablet once weekly.
- Pediatric patients: Approximately 5 mg/kg body weight once weekly. Prophylactic drug administration should begin 1 week before arrival in an endemic area, and should be continued for 4 additional weeks after leaving the area to ensure suppressive blood levels of the drug when merozoites emerge from the liver 2, 3.
From the Research
Malaria Prophylaxis Recommendations
The following are recommendations for malaria prophylaxis based on available evidence:
- Atovaquone/proguanil is a highly effective option for the prevention of Plasmodium falciparum malaria, including drug-resistant strains 4.
- The combination of atovaquone and proguanil provides causal prophylaxis, eliminating the need to continue post-travel treatment beyond 7 days 4.
- Atovaquone/proguanil is generally well tolerated, with fewer gastrointestinal adverse events than chloroquine plus proguanil, and fewer neuropsychiatric adverse events than mefloquine 4, 5.
- Other options for chemoprophylaxis include doxycycline and mefloquine, with selection based on patient characteristics and preferences 6, 5.
- The choice of drug for prevention of P. falciparum malaria depends on the risk of chloroquine resistance, and possibly mefloquine resistance 7.
Specific Recommendations
- For nonimmune adults, adolescents, and children (≥11 kg) visiting malaria-endemic regions for ≤28 days, atovaquone/proguanil (250/100 mg in adults and dosage based on bodyweight in children <40 kg) once daily is recommended 4.
- For individuals from endemic regions who may carry some immunity to malaria (semi-immune), the prophylactic efficacy rating for atovaquone/proguanil is 95-100% 4.
- Atovaquone-proguanil is also effective as prophylaxis in areas with high prevalence of chloroquine resistance, although it should only be used as a second-line option after mefloquine for short-term prophylaxis 7.
Comparison of Prophylaxis Options
- Atovaquone-proguanil compared to doxycycline had similar adverse events reported, while atovaquone-proguanil users had fewer reports of adverse effects compared to mefloquine users 5.
- Doxycycline users had fewer reported neuropsychiatric events than mefloquine users 5.
- Chloroquine-proguanil had more reports of adverse effects and gastrointestinal adverse effects compared to atovaquone-proguanil and doxycycline 5.