Orladeyo (berotralstat) is an oral, once-daily prescription medication used for the routine prevention of hereditary angioedema (HAE) attacks in adults and pediatric patients 12 years and older. It works by inhibiting plasma kallikrein, a protein involved in the pathway that causes swelling associated with HAE. By reducing kallikrein activity, Orladeyo helps decrease the frequency of HAE attacks. It is intended for preventive treatment and is not used to treat an acute HAE attack.