Is Buspar (buspirone) safe to use during breastfeeding?

Buspirone Safety During Breastfeeding

Buspirone (Buspar) is safe to use during breastfeeding due to minimal transfer into breast milk and a low relative infant dose that poses minimal risk to breastfed infants. 1

Evidence on Buspirone in Breastfeeding

Recent research provides strong evidence supporting buspirone's safety during lactation:

• A 2024 study found that buspirone was below detectable levels (1.5 ng/mL) in breast milk across all samples, even at doses up to 30 mg twice daily 1
• The active metabolite (1-PP) was detected at very low levels
• The relative infant dose (RID) ranged from 0.21% to 2.17%, well below the 10% safety threshold 1
• No adverse effects were reported in exposed infants 1

Pharmacological Considerations

Buspirone offers several advantages as an anxiolytic for breastfeeding mothers:

• Unlike benzodiazepines, buspirone has minimal risk of:
  • Dependence
  • Respiratory depression
  • Sedation in the infant
• The FDA labeling does not specifically contraindicate buspirone during breastfeeding 2
• The extremely low milk transfer makes it preferable to other anxiolytics like diazepam, which should be avoided during lactation

Clinical Recommendations

When prescribing buspirone to breastfeeding mothers:

1. Start with the lowest effective dose
2. Take medication immediately after breastfeeding to maximize clearance time before the next feeding
3. Monitor the infant for:
   • Unusual drowsiness
   • Changes in feeding patterns
   • Irritability
   • Sleep disturbances

Comparison with Other Anxiolytics

Buspirone offers safety advantages over other anxiolytics during breastfeeding:

• Short-acting benzodiazepines like midazolam and lorazepam are preferred over diazepam if needed, but buspirone is generally safer than any benzodiazepine 3
• Older literature (1978-1993) cautioned against many psychotropic medications during breastfeeding 4, 5, 6, but these recommendations are outdated compared to recent evidence

Important Considerations

• Exercise caution in neonates and young infants (<6 weeks) due to their immature hepatic metabolism 3
• Older infants (>6 months) generally have more mature metabolism and are at lower risk for adverse effects 3
• Avoid combining buspirone with other CNS-active drugs unless clinically necessary 2

Potential Drug Interactions

If the breastfeeding mother is taking other medications, be aware that:

• Diltiazem, verapamil, and erythromycin can increase buspirone concentrations 2
• Buspirone should not be combined with MAOIs 2
• Unlike the case reported with bupropion and escitalopram 7, there are no reports of seizures in infants exposed to buspirone through breast milk

Human milk research consistently shows that buspirone's minimal transfer into breast milk makes it a safe option for treating anxiety in breastfeeding mothers, with benefits of maternal treatment typically outweighing the minimal risks to the infant.