Currently, breastfeeding is not contraindicated in women using psychotropic medications such as benzodiazepines. Dr. Gideon Koren from the Hospital for Sick Children, Toronto, Canada and colleagues say their study “supports the continued recommendation to initiate breastfeeding while taking benzodiazepines postpartum.”
Their study population included 124 mothers who called the Motherisk Program at the Hospital for Sick Children between January 2010 and May 2011 seeking information on the effects of benzodiazepines on their infants during lactation. The most commonly used benzodiazepines during lactation were lorazepam (52%), clonazepam (18%), and midazolam (15%).
At the time of follow-up, the children were between 2 and 24 months old (average age, 11 months). The researchers say adverse outcomes, specifically sedation, occurred in only 2 of 124 infants or 1.6%. “In both sedated infants, mothers used drugs that are not among the most commonly prescribed in this class,” the authors note.
One mother reported using 0.25 mg of alprazolam on two occasions, and the other mother reported chronic use of 0.25 mg clonazepam twice per day and 1 mg of flurazepam daily. Sedation in these two cases was not associated with benzodiazepine dose, number of hours breastfed, or any demographic trait.
The only significant difference seen between mothers who reported adverse drug outcomes in their children and those who did not was the total number of CNS depressants taken. Those who reported sedated infants were taking a mean of 3.5 medications that cause CNS depression compared with a mean of 1.70 in those with no health concerns related to benzodiazepine use during lactation (p=0.006). [pg2col2]
The first mother with a sedated infant was taking 50 mg of sertraline daily and 2.5 mg of zopiclone when necessary, or about once every three days. The second mother reporting a sedated infant was co-medicating with 1 mg of bupropion and 0.75 mg of risperidone.
Thirty two of the 124 mothers (26%) reported adverse outcomes in themselves, including sedation, confusion, headache, nausea, and vomiting; this was common in mothers taking a greater number of CNS depressants.
The researchers say, “More work is needed to investigate brain penetration of benzodiazepines in neonates.” For now, they say the results support the continued use of benzodiazepines during breastfeeding when necessary. They say limiting the number of CNS depressants taken while breastfeeding will further decrease the risk of both maternal and infant adverse outcomes.
The authors have stated that they have no potential conflicts of interest. Funding for the study was provided by the University of Western Ontario, the Canadian Pharmacogenomics Network for Drug Safety and the Canadian Institutes of Health Research.