proguanil

Proguanil

Proguanil, also known as chlorguanide and chloroguanide, is a medication used to treat and prevent malaria. It is often used together with chloroquine or atovaquone. When used with chloroquine the combination will treat mild chloroquine resistant malaria. It is taken by mouth. Side effects include diarrhea, constipation, skin rashes, hair loss, and itchiness. Because malaria tends to be more severe in pregnancy, the benefit typically outweighs the risk. If used during pregnancy it should be taken with folate. It is likely safe for use during breastfeeding. Proguanil is converted by the liver to its active metabolite, cycloguanil. It was removed from the World Health Organization's List of Essential Medicines in 2025. In the United States and Canada it is only available in combination as atovaquone/proguanil.