Bupropion and Breastfeeding
Bupropion can be used during breastfeeding with caution, but close monitoring of the infant for seizures is essential given two case reports of seizures in breastfed infants, despite generally low drug transfer into milk. 1
Drug Transfer and Infant Exposure
Bupropion is present in human milk and has been detected in infant serum, though typically at very low or undetectable levels 1. The FDA label confirms that bupropion and its metabolites transfer into breast milk, with average daily infant exposure estimated at only 2% of the maternal weight-adjusted dose 2. Research demonstrates that milk-to-plasma ratios range from 2.51 to 8.58, indicating drug accumulation in breast milk at concentrations higher than maternal plasma 3. However, in one study of two mother-infant pairs, neither infant had quantifiable serum levels of bupropion or hydroxybupropion at steady state 4.
Critical Safety Concern: Seizure Risk
The most important safety consideration is the risk of seizures in breastfed infants. The 2024 AJOG guideline explicitly states there have been 2 case reports of seizures in breastfed infants exposed to bupropion 1. One detailed case report describes a 6.5-month-old infant who experienced severe emesis and tonic seizure-like symptoms while exposed to bupropion (and escitalopram) through breastfeeding 5. Notably, the infant's serum concentrations of bupropion and hydroxybupropion were lower than the reported therapeutic range, suggesting infants may have heightened susceptibility to the epileptogenic effects of bupropion compared to adults 5.
The FDA label acknowledges that "postmarketing reports have described seizures in breastfed infants," though it notes "the relationship of bupropion exposure and these seizures is unclear" 2.
Clinical Recommendation
If bupropion is necessary during breastfeeding:
Counsel parents explicitly about the seizure risk documented in case reports
Monitor the infant closely for:
- Any seizure activity or seizure-like movements
- Excessive irritability or jitteriness
- Feeding difficulties or vomiting
- Changes in sleep patterns or unusual lethargy
Consider the risk-benefit ratio carefully, particularly if:
- The infant has any risk factors for seizures
- The mother requires higher doses of bupropion
- Alternative antidepressants with better lactation safety profiles could be effective
Avoid polytherapy when possible, as the case report involved concurrent escitalopram use, which may have contributed through CYP2D6 inhibition 5
Evidence Quality and Limitations
The data supporting bupropion use during breastfeeding is very limited (21 cases) according to the 2024 AJOG guideline 1. While most exposed infants had no reported adverse events, the two seizure cases represent a serious potential risk that cannot be dismissed. The guideline's designation of "caution is advised" reflects this limited evidence base and the documented serious adverse events.
Alternative Considerations
Given the seizure risk and limited safety data, consider alternative antidepressants with more robust lactation safety profiles (such as sertraline or paroxetine) if clinically appropriate for the mother's condition. The decision to use bupropion should weigh the mother's clinical need against the potential—albeit rare—risk of serious adverse effects in the infant 2.