Gruber LM, Jasim S, Ducharme-Smith A, et al. - Since preintervention titration of alpha- and beta-adrenergic blockade is needed for the treatment of pheochromocytoma and paraganglioma (PPGL), but patients may still be at risk for complications from catecholamine excess, researchers investigated the role of metyrosine in the treatment of patients with pheochromocytoma and paraganglioma. A systematic literature review was conducted (Ovid Medline and Scopus databases) on December 17, 2019, including studies with humans and original data. When used for a limited period of time, metyrosine is well tolerated and can improve intraoperative outcomes in PPGL. The majority of patients experience sedation as a side effect, which is usually mild and self-limiting. Metyrosine is a safe addition to traditional alpha-adrenergic and beta-adrenergic blockade and should be considered in patients with PPGL who are at high risk for acute catecholamine release.