Pregabalin Safety in Lactating Women
Breastfeeding is not recommended during pregabalin treatment due to the potential risk of tumorigenicity in the breastfed infant, despite relatively low drug transfer into breast milk.
FDA Drug Label Recommendation
The FDA explicitly states that breastfeeding is not recommended during treatment with pregabalin due to potential tumorigenicity risk based on animal studies, even though the clinical significance in humans remains unclear 1.
Key Pharmacokinetic Data from FDA Label:
- Pregabalin is detected in breast milk at average steady-state concentrations approximately 76% of maternal plasma levels 1
- The estimated average daily infant dose from breast milk is 0.31 mg/kg/day, which represents approximately 7% of the weight-adjusted maternal dose 1
- This calculation assumes mean milk consumption of 150 mL/kg/day 1
Supporting Research Evidence
The primary pharmacokinetic study in lactating women confirms the FDA's data:
- Ten healthy lactating women (≥12 weeks postpartum) received pregabalin 150 mg every 12 hours (300 mg daily) 2
- Mean amount of pregabalin recovered in breast milk over 24 hours was 574 μg (range 270-1720 μg), representing only 0.2% of the administered daily maternal dose 2
- The relative infant dose (RID) was approximately 7% of the maternal dose, which is generally below the theoretical 10% safety threshold used for many medications 2, 3
Critical Safety Concern: Tumorigenicity
The primary concern is not acute toxicity but rather theoretical long-term tumorigenicity risk:
- Animal studies demonstrate a potential risk of tumor development with pregabalin exposure 1
- Available clinical data in patients >12 years of age do not provide clear conclusions about tumorigenicity risk in humans 1
- The FDA emphasizes this uncertainty as the basis for recommending against breastfeeding 1
Clinical Context
While pregabalin was well-tolerated in the lactating women studied with only mild-to-moderate adverse events 2, and physiologically-based pharmacokinetic modeling suggests relatively low infant exposure 3, the theoretical carcinogenic risk outweighs the relatively favorable pharmacokinetic profile.
Common Pitfall to Avoid:
Do not be reassured solely by the low RID of 7% or the small absolute amount transferred to breast milk. The FDA's recommendation is based on the nature of the potential harm (tumorigenicity) rather than the quantity of drug exposure 1.
Alternative Approach
If pain management or seizure control is needed in a lactating woman:
- Consider alternative medications with established safety profiles during lactation
- The 2020 Association of Anaesthetists guideline provides extensive guidance on analgesics compatible with breastfeeding, including morphine, ibuprofen, diclofenac, and paracetamol 4
- For neuropathic pain specifically, consult with specialists about safer alternatives before defaulting to pregabalin
If pregabalin is deemed absolutely necessary, the mother should discontinue breastfeeding during treatment 1.