C1 inhibitors are used to treat hereditary angioedema (HAE), a rare genetic disorder that causes severe swelling. Some C1 inhibitors treat HAE attacks, while others are used to prevent them over time. These medications work by replacing missing or malfunctioning C1 inhibitor proteins in your body. C1 inhibitors are available in injectable forms. Examples include C1 esterase inhibitor, human (Berinert, Cinryze, Haegarda) and C1 esterase inhibitor, recombinant (Ruconest).
