Promacta (generic: eltrombopag) is a prescription medication used to prevent bleeding episodes in patients with chronic immune (idiopathic) thrombocytopenia (ITP) or chronic hepatitis C virus (HCV). Promacta belongs to a group of drugs called thrombopoietin receptor agonist, which work by causing the cells of the bone marrow to produce more platelets (cells that are needed for blood to clot).

This medication comes in tablet form and is taken once a day, on an empty stomach.

Common side effects of Promacta include nausea, diarrhea, runny or stuffy nose, and muscle aches.