Agent

Dosage and prophylactic regimen

Remarks

Atovaquone/proguanil

Atovaquone 250 mg/proguanil hydrochloride 100 mg PO every day; initiate prophylaxis 1-2 days before arrival to an endemic area; continue throughout stay and 7 days thereafter

Effectively prevents malaria in the majority of endemic regions and areas in Southeast Asia with multidrug resistance; its mechanism of action allows for early discontinuation of chemoprophylaxis after travel

Chloroquine

A single dose of chloroquine diphosphate 500 mg PO every week; initiate prophylaxis ≥1 week before arrival to an endemic area; continue throughout stay and 4 weeks thereafter

Due to common drug resistance of P falciparum, chloroquine is currently considered ineffective prophylaxis in the majority of endemic regions, including Africa; use of chloroquine is limited to certain countries in Latin America, Middle East, and China; long-term use may cause damage to the retina

Doxycycline

100 mg PO every day; initiate prophylaxis 1-2 days before arrival to an endemic area; continue throughout stay and 4 weeks thereafter

Effectively prevents malaria in the majority of endemic regions and areas in Southeast Asia with multidrug resistance; due to risk of phototoxicity, avoid excessive sunlight exposure during agent intake and apply UV protection products

Mefloquine

A single dose of 250 mg PO every week; initiate prophylaxis ≥1 week before arrival to an endemic area; continue throughout stay and 4 weeks thereafter

Limited use due to drug resistance of P falciparum in Southeast Asia and risk of neuropsychiatric adverse effects; can be used by pregnant women