Drug	Dosage		Comments
Chloroquine-sensitive malaria
Chloroquine (Aralen)	Begin 1 to 2 weeks before travel and continue for 4 weeks after leaving malaria-endemic area Adults: 500 mg salt (equal to 300 mg base) once per week Children: 8.3 mg salt (equal to 5 mg base) per kg per week, up to adult dosage		Used for prophylaxis in Mexico and Central America (west of the Panama Canal), and the island of Hispaniola (Haiti and the Dominican Republic) In the United States, hydroxychloroquine may be better tolerated Chloroquine may exacerbate psoriasis
Hydroxychloroquine (Plaquenil)	Begin 1 to 2 weeks before travel and continue for 4 weeks after leaving malaria-endemic area Adults: 400 mg salt (equal to 310 mg base) once per week Children: 6.5 mg salt (equal to 5 mg base) per kg per week, up to adult dosage
Chloroquine-resistant malaria
Atovaquone/proguanil (Malarone)	Begin 1 to 2 days before travel and continue for 1 week after leaving malaria-endemic area Adults: 250 mg/100 mg per day Children: 1 tablet = 62.5 mg/25 mg per day < 5 kg: not recommended 5 to 8 kg: one-half of a children's tablet daily 9 to 10 kg: three-fourths of a children's tablet daily 11 to 20 kg: 1 children's tablet daily 21 to 30 kg: 2 children's tablets daily 31 to 40 kg: 3 children's tablets daily > 40 kg: 1 adult tablet daily		Useful in regions of mefloquine resistance Contraindicated in patients with severe renal impairment (a creatinine clearance < 30 mL per minute per 1.73 m² [0.50 mL per second per m²]); high cost makes this drug less desirable for longer trips Avoid in pregnant women and mothers who are breastfeeding infants weighing < 11 lb (5 kg) Should be taken with food or a milky drink
Doxycycline	Begin 1 to 2 days before travel and continue for 4 weeks after leaving malaria-endemic area Adults: 100 mg once per day Children: 2 mg per kg per day, up to the adult dosage		Useful in regions of mefloquine resistance Contraindicated in children younger than 8 years, and in pregnant and lactating women May cause nausea, photosensitivity, vaginal yeast infections, and esophageal ulceration
Mefloquine	Begin ≥ 2 weeks before travel and continue for 4 weeks after leaving malaria-endemic area Adults: 250 mg salt (equal to 228 mg base) once per week Children: ≤ 9 kg: 5 mg per kg (4.6 mg per kg base) once per week > 9 to 19 kg: one-fourth of 250-mg tablet weekly 20 to 30 kg: one-half of 250-mg tablet weekly 31 to 45 kg: three-fourths of 250-mg tablet weekly > 45 kg: 250 mg once per week		Contraindications include epilepsy, psychiatric conditions (including anxiety and depression), and cardiac conduction disorders; may be used in all trimesters of pregnancy

*Short-term travel to areas with more than 90% Plasmodium vivax* malaria (e.g., Central and South America)**
Primaquine	Begin 1 to 2 days before travel and continue for 1 week after leaving malaria-endemic area Adults: 52.6 mg salt (equal to 30 mg base) once per day Children: 0.8 mg per kg salt (equal to 0.5 mg per kg base) once per day, up to adult dosage		Screen for G6PD deficiency before use; can be fatal if taken by patients who are G6PD negative Contraindicated in pregnant women, and in breastfeeding mothers unless the infant has a documented normal G6PD level Not commonly used relative to other prophylactic drugs