Hypnotic
PREGNANCY RECOMMENDATION: Human Data Suggest Risk in 1st and 3rd Trimesters
BREASTFEEDING RECOMMENDATION: No Human Data—Potential Toxicity
PREGNANCY SUMMARY
No reports describing the use of estazolam in human pregnancy have been located. The effects of this drug on the fetus should be similar to other benzodiazepines (see Diazepam). Maternal use near delivery may potentially cause neonatal motor depression and withdrawal.
FETAL RISK SUMMARY
Estazolam is a benzodiazepine hypnotic agent in the same general class as flurazepam, quazepam, temazepam, and triazolam. It is indicated for the short-term management of insomnia. The metabolites have low potencies and concentrations and are not significant contributors to the hypnotic activity of estazolam. Plasma protein binding of estazolam is high (93%) and the range of estimated elimination half-life varies from 10 to 24 hours (1).
Animal reproduction studies have apparently not been conducted with estazolam. The manufacturer considers the drug contraindicated in pregnancy (1).
It is not known if estazolam crosses the human placenta. The molecular weight (about 295) and moderately long elimination half-life suggest that the drug will be transferred to the embryo–fetus. Of note, the benzodiazepine, diazepam, freely crosses the placenta and accumulates in the fetal circulation (see Diazepam).
BREASTFEEDING SUMMARY
No reports describing the use of estazolam during human lactation have been located. The molecular weight (about 295) and moderately long elimination half-life (10–24 hours) suggest that the drug will be excreted into breast milk. Other agents in this class are excreted into milk in low concentrations (e.g., see Quazepam and Temazepam). No toxicity was observed in the nursing infants exposed to these two agents. However, the effects, if any, on an infant’s CNS function are unknown. In recognition of this, the American Academy of Pediatrics classified quazepam and temazepam, especially when taken by nursing mothers for long periods, as agents whose effects on an infant are unknown, but may be of concern. Estazolam should be classified similarly.
Reference
1.Product information. ProSom. Abbott Laboratories, 2004.