Clinically significant anxiety symptoms are common during the postpartum period and frequently complicate the treatment of postpartum depression. While SSRIs are indicated for the treatment of anxiety symptoms, especially when they co-occur with depression, many women may need to use a benzodiazepine for managing more severe symptoms of anxiety or insomnia.
An early study from Birnbaum and colleagues at the CWMH included 11 infants exposed to clonazepam (Klonopin) and an antidepressant. No adverse events were reported in this sample. Benzodiazepines were not detected in infant serum when mothers had taken these benzodiazepines only during the postpartum period.
In a subsequent meta-analysis including 21 nursing infants exposed to benzodiazepines (Rubin 2004), adverse events were reported in four (or 19.0%) of the exposed infants. Reported adverse events included lethargy, irritability, poor weight gain, and respiratory distress.
The largest study from the Motherisk program helps to clarify the risks associated with benzodiazepines in breastfeeding mothers, including a total of 124 exposed infants. Women who contacted the Motherisk program with questions regarding the use of benzodiazepines during lactation were recruited into the study. In a follow-up telephone interview, information regarding medication use, frequency of breastfeeding, the health of their infants, and demographic characteristics was collected.
The most commonly used benzodiazepines were lorazepam (52%), clonazepam (18%), and midazolam (15%). About half of the women (n=60) were also taking other medications, most commonly antidepressants and opioids, in addition to the benzodiazepines. The mean age of the children at the time of follow-up was 11 months (range 2-24 months). Adverse events, specifically sedation, were observed in only 1.6% (2 of 124) infants exposed.
One of the women with a sedated infant reported using alprazolam 0.25 mg on two occasions. She was also taking sertraline 50 mg and zopiclone 2.5 mg daily. The other woman was on clonazepam 0.25 mg twice daily, flurazepam 1 mg, risperidone 0.75 mg, and bupropion. The authors observed that the women reporting sedation in their infants were taking more psychotropic medications than the women who did not report adverse events in their children.
In addition to these studies, LactMed includes several case reports of sedation in infants exposed to benzodiazepines via breast milk.
Clinical Implications
With the exception of one study (Rubin et al, 2004), these studies indicate that the risk of adverse events in nursing infants exposed to benzodiazepines in breast milk is very low. Studies that have quantified levels of benzodiazepines in infants’ serum have demonstrated low or undetectable levels of benzodiazepines. Adverse events have been reported in breastfeeding infants exposed to benzodiazepines in the breast milk; however, they do not appear to be serious, with sedation being the most commonly reported adverse event.
Although the information regarding benzodiazepines and breastfeeding is somewhat limited, there does not appear to be a significant risk of serious adverse events. Based on these data, benzodiazepines would be a reasonable treatment option for breastfeeding women with anxiety or insomnia. Exposed infants should be monitored for sedation, especially if the mother is taking higher doses of benzodiazepines or other, potentially sedating, medications.
Ruta Nonacs, MD PhD
References
Kelly L, Poon S, Madadi P, Koren G. Neonatal Benzodiazepines Exposure during Breastfeeding. J Pediatr. 2012.
