Methyldopa

pharmacological · nervous · cardiovascular · digestive · immune-hematologic · Oral · IV

Methyldopa. Centrally-acting α2-adrenergic agonist (active metabolite α-methylnorepinephrine) — reduces sympathetic outflow. Preferred… Oral half-life 1.3 h.

Centrally-acting α2-adrenergic agonist (active metabolite α-methylnorepinephrine) — reduces sympathetic outflow. Preferred antihypertensive in pregnancy with the longest safety record. Hemolytic anemia + hepatotoxicity at chronic use.

PK: F 0.25 is verbatim and stands (PMID:781212, eleven subjects). The half-life is corrected 2 -> 1.28 h, the beta-phase figure in normal subjects, and V 28 L becomes 42 L from 0.60 L/kg — both from PMID:7047042, a review, so they are flagged as review-grade. THE STORED V WAS ALSO BYTE-IDENTICAL TO TERAZOSIN 28 L, an unrelated drug, which is what drew this record into the batch. ka 1 /h dropped. EFFECT IS DECOUPLED FROM PLASMA: the antihypertensive effect half-life is about 10 hours against a plasma curve of 1.28 h (PMID:7093115), because the active species is alpha-methylnoradrenaline formed centrally.

Pharmacokinetics

• Oral — t½ 1.3 h · F 25% · Vd 42 L
• IV — t½ 1.3 h · F 100% · Vd 42 L

Sources: PMID:781212, PMID:7047042, PMID:7093115