title: Placental transfer and perinatal pharmacokinetics of betaxolol.
abstract: Betaxolol levels in blood were monitored in the perinatal period in 28 pregnant hypertensive women and in their babies. In the mothers betaxolol concentrations at delivery ranged from less than 1 to 115 ng.ml-1 after doses of 10 to 40 mg.day-1. The apparent blood half-life was 15.6 to 22.1 h mean (19 h). Umbilical cord levels indicated a rapid equilibrium between fetal and maternal units (ratio 0.93) within few hours after dosing. Milk betaxolol concentrations, measured in few cases, exceeded those in blood by a factor of 3. Amniotic fluid concentrations were similar to those observed in maternal venous blood and umbilical cord blood. In neonates, the blood betaxolol half-life ranged from 14.8 to 38.5 h, with a definite trend towards a negative correlation with gestational age. A 11-61% rise in the betaxolol concentration was observed in 64% of the neonates during the first 12 h of extrauterine life. The data indicate that betaxolol kinetics is not altered in pregnant women and they stress the need for careful and prolonged (72-96 h) intensive monitoring of neonates born to hypertensive mothers treated with beta-blocking agents.
authors.affiliation: Clinical Research Department, Synthelabo Recherche, Paris, France.
authors.forename: P L
authors.initials: PL
authors.lastname: Morselli
authors.forename: M J
authors.initials: MJ
authors.lastname: Boutroy
authors.forename: G
authors.initials: G
authors.lastname: Bianchetti
authors.forename: A
authors.initials: A
authors.lastname: Zipfel
authors.forename: J L
authors.initials: JL
authors.lastname: Boutroy
authors.forename: P
authors.initials: P
authors.lastname: Vert
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000378:metabolism; D015784:Betaxolol / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005312:Fetal Blood / Q000378:metabolism; D006207:Half-Life; D006801:Humans; D006973:Hypertension / Q000188:drug therapy; D007231:Infant, Newborn; D007743:Labor, Obstetric; D008297:Male; D008431:Maternal-Fetal Exchange; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000188:drug therapy
chemical_list: D015784:Betaxolol