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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.

Twenty two pregnant women with mild to moderate hypertension were treated with betaxolol (10-40 mg/day), a cardioselective beta adrenoceptor blocking agent. The analysis of the changes from the baseline confirmed the antihypertensive effect of the drug with a mean decrease in SBP of 11.8 mm Hg and in DBP of 8.3 mm Hg. A diastolic BP less than 90 mm Hg was obtained in 20 patients after the first day of therapy. Fetal safety, assessed by ultrasonography and cardiotocographic recording was excellent. The 22 mothers gave birth to 23 live born babies (one twin pregnancy). Mean Apgar scores were 8.3 and 9.1 at 1 and 5 min. Only 1 newborn had an Apgar score less than 7. Three newborns suffered from fetal distress and 1 from threat for causes not related to therapy. At 9 months follow-up, all 23 babies were in good health. These data suggest that betaxolol is effective in reducing maternal blood pressure without any deleterious effect on the foetus and the newborn.

The efficacy and the safety of betaxolol (BTX), a cardio-selective adrenoceptor blocking agent with a long half life, was tested in 22 hypertensive pregnant women. BTX doses varied from 10 to 40 mg/day. BTX given as monotherapy (n = 19) or associated to dihydralazine (n = 3) led to a satisfactory control of arterial blood pressure (ABP). In the mother, the drug was very well tolerated. (table; see text) The fetal safety, evaluated by mean of cardiotocography and echography was also satisfactory. Fetal heart rythm was significantly slowed following first intake of BTX and remained stable until delivery; there was only one case of intra-uterine growth retardation pre-existing to the pharmacological treatment. Nine deliveries were ceasarian [fetal distress (n = 1); poor control ABPI (n = 1); obstetrical reasons (n = 7)]. Seventeen neonates were full-term and six were premature (twins included). The state of neonates at birth was very satisfactory (Apgar at 5 minutes greater than 9 in 21/23). Glycemia less than 1.66 mmoles/1 in two neonates, was normal within 24 to 48 hours. In conclusion, BTX was very efficacious in controlling increased blood pressure in pregnant women and its safety in the mother, the fetus and the newborn was very good.