Common side effects include vomiting, headache, and dizziness.[4] Other side effects may include methemoglobinemia, trouble sleeping, and anaphylaxis.[4] In people with G6PD deficiency, red blood cell breakdown may occur.[4] Use in pregnancy is not recommended.[4] Tafenoquine is in the 8-aminoquinoline family of medications.[3] How it works is unclear but it is effective both in the liver and blood.[4][3]