Primaquine is a medication used to treat and prevent malaria and to treat Pneumocystis pneumonia. Specifically it is used for malaria due to Plasmodium vivax and Plasmodium ovale along with other medications and for prevention if other options cannot be used. It is an alternative treatment for Pneumocystis pneumonia together with clindamycin. It is taken by mouth.
Common side effects include nausea, vomiting, and stomach cramps. Primaquine should not be given to people with glucose-6-phosphate dehydrogenase (G6PD) deficiency due to the risk of red blood cell breakdown. It is often recommended that primaquine not be used during pregnancy. It may be okay in breastfeeding when the baby is known not to have G6PD deficiency. The mechanisms of action is not entirely clear but is believed to involve effects on the malaria parasites DNA.
Primaquine was first made in 1946. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. It is available as a generic medication. The wholesale cost in the developing world is 0.04 to 0.11 USD per day. In the United States a typical course of treatment is 50 to 100 USD.