From the Guidelines
For malaria prophylaxis, I recommend atovaquone-proguanil (Malarone), doxycycline, or mefloquine based on the destination's specific malaria risk and resistance patterns.
Key Considerations
- Atovaquone-proguanil is taken daily starting 1-2 days before travel, throughout the stay, and for 7 days after leaving the malaria-endemic area. The adult dose is one tablet (250mg/100mg) daily.
- Doxycycline is taken at 100mg daily, starting 1-2 days before travel, during the stay, and for 4 weeks after departure.
- Mefloquine is taken weekly at 250mg, starting 2-3 weeks before travel, during the stay, and for 4 weeks after leaving. The choice between these medications depends on the traveler's destination, medical history, pregnancy status, and drug interactions, as noted in studies such as 1.
Additional Measures
Beyond medication, advise patients to:
- Use insect repellent containing DEET
- Wear long sleeves and pants during evening hours
- Sleep under insecticide-treated bed nets
- Use air conditioning when available These preventive measures work by either killing the Plasmodium parasite before it can establish infection or by preventing mosquito bites that transmit the parasite, as discussed in 1.
Special Considerations
Chloroquine (500mg weekly) may be used in the few areas without chloroquine resistance, but its use is limited due to widespread resistance, as mentioned in 1 and 1. It's essential to consider the specific malaria risk and resistance patterns of the destination, as well as the individual's medical history and other factors, to choose the most appropriate prophylaxis regimen, as emphasized in 1.
From the FDA Drug Label
Malaria Prophylaxis in Adults Dosage: One 250 mg mefloquine hydrochloride tablet once weekly. Prophylactic drug administration should begin 1 week before arrival in an endemic area. Subsequent weekly doses should be taken regularly, always on the same day of each week, preferably after the main meal To reduce the risk of malaria after leaving an endemic area, prophylaxis must be continued for 4 additional weeks to ensure suppressive blood levels of the drug when merozoites emerge from the liver.
Malaria Prophylaxis in Pediatric Patients The recommended prophylactic dose of mefloquine hydrochloride is approximately 5 mg/kg body weight once weekly. One 250 mg mefloquine hydrochloride tablet should be taken once weekly in pediatric patients weighing over 45 kg In pediatric patients weighing less than 45 kg, the weekly dose decreases in proportion to body weight: 30 to 45 kg: 3/4 tablet 20 to 30 kg: 1/2 tablet
For malaria prophylaxis, the patient can be given mefloquine. The dosage is as follows:
- For adults: one 250 mg tablet once weekly.
- For pediatric patients:
- Weighing over 45 kg: one 250 mg tablet once weekly.
- Weighing 30 to 45 kg: 3/4 tablet once weekly.
- Weighing 20 to 30 kg: 1/2 tablet once weekly. Prophylaxis should begin 1 week before arrival in an endemic area and continue for 4 additional weeks after leaving. Alternatively, doxycycline can be used for malaria prophylaxis. The dosage is:
- 100 mg daily, starting 1 to 2 days before travel and continuing daily while in the malarious area and after leaving for 4 further weeks 2 3.
From the Research
Malaria Prophylaxis Options
The following are some options for malaria prophylaxis:
- Atovaquone/proguanil: a fixed-dose combination tablet of two antimalarial agents, highly effective for the prevention of Plasmodium falciparum malaria 4
- Mefloquine: one of four antimalarial agents commonly recommended for preventing malaria in travellers to malaria-endemic areas, with high efficacy but controversy about its psychological side effects 5
- Doxycycline: an alternative recommended antimalarial agent, with a different side effect profile compared to mefloquine 5
- Chloroquine-proguanil: a combination of two antimalarial agents, widely used for malaria chemoprophylaxis despite low effectiveness in areas where multidrug-resistant malaria occurs 6
- Primaquine: a chemoprophylactic agent of choice for areas with high co-circulation of P. falciparum and P. vivax, particularly effective against late, hypnozoite reactivation-related attacks 7
Efficacy and Safety of Malaria Prophylaxis Options
The efficacy and safety of these options vary:
- Atovaquone/proguanil: highly effective against P. falciparum, with a causal prophylactic efficacy rating of 95-100% in semi-immune individuals, and generally well tolerated with fewer gastrointestinal adverse events compared to chloroquine-proguanil and fewer neuropsychiatric adverse events compared to mefloquine 4, 6
- Mefloquine: highly effective against P. falciparum, but with a higher risk of discontinuation due to adverse effects, including abnormal dreams, insomnia, anxiety, and depressed mood, compared to atovaquone-proguanil and doxycycline 5
- Doxycycline: effective against P. falciparum, with a similar efficacy to mefloquine, but with a different side effect profile, including a higher risk of dyspepsia, photosensitivity, vomiting, and vaginal thrush 5
Considerations for Choosing a Malaria Prophylaxis Option
The choice of antimalarial agent depends on individual factors, including:
- The importance of specific adverse effects
- Pill burden
- Cost
- The risk of malaria in the destination area
- The individual's medical history and personal preferences 5