[The hydrochloride salt form of methyldopa, a phenylalanine derivate and aromatic amino acid decarboxylase inhibitor with antihypertensive activity. Methyldopa is a prodrug and is metabolized in the central nervous system. The antihypertensive action of methyldopa seems to be attributable to its conversion into alpha-methylnorepinephrine, which is a potent alpha-2 adrenergic agonist that binds to and stimulates potent central inhibitory alpha-2 adrenergic receptors. This results in a decrease in sympathetic outflow and decreased blood pressure. ( NCI )] (UMLS (NCI) C0304527) =Organic Chemical; Pharmacologic Substance =METHYLDOPATE; =METHYLDOPATE HYDROCHLORIDE 50 MG/ML