Sympatholytic (Antiadrenergic)
PREGNANCY RECOMMENDATION: Limited Human Data—Animal Data Suggest Moderate Risk
BREASTFEEDING RECOMMENDATION: No Human Data—Potential Toxicity
PREGNANCY SUMMARY
One report describing the use of doxazosin in human pregnancy has been located.
FETAL RISK SUMMARY
Doxazosin is a peripherally acting α1-adrenergic blocking agent used in the treatment of hypertension.
No adverse fetal effects were observed when pregnant rats and rabbits were given oral doses 4 and 10 times the human serum levels achieved with a 12 mg/day therapeutic dose (HD), respectively. However, reduced fetal survival occurred in rabbits dosed at 20 times the HD and delayed postnatal development was observed in rat pups whose mothers were given doses 8 times the HD during the perinatal and postnatal periods. Doxazosin crosses the placenta in rats (1).
It is not known if doxazosin crosses the human placenta. The molecular weight (about 548) suggests that the drug will cross to the embryo and/or fetus.
In a 2012 report, a 36-year-old pregnant woman developed pheochromocytoma at 26 weeks’ (2). She was initially treated with proroxan (an alpha adrenergic blocker not available in the United States) (15 mg three times daily). Eleven days after treatment started, her condition worsened and doxazosin (dose not specified), a calcium channel blocker (name and dose not specified), and an ACE inhibitor (name and dose not specified) were added. The four-drug combination was continued until a cesarean section was performed at 30 4/7 weeks’ gestation to deliver a 1.700-kg male infant. A simultaneous laparatomic right-sided adrenalectomy also was performed. Apgar scores were 6 and 8 at 1 and 5 minutes, respectively. No further details on the premature infant were provided. The woman underwent a hysterectomy for placenta increta (2).
BREASTFEEDING SUMMARY
No reports describing the use of doxazosin during human lactation have been located.
References
1.Product information. Cardura. Pfizer, 2000.
2.Pirtskhalava N. Pheochromocytoma and pregnancy: complications and solutions (case report). Georgian Med News 2012;208–9:76–82.