Is Cymbalta (duloxetine) safe for nursing mothers?

Duloxetine (Cymbalta) and Breastfeeding

Duloxetine should be used with caution during breastfeeding, with careful monitoring of the infant for sedation, poor feeding, and poor weight gain. 1

Safety Profile in Breastfeeding

Duloxetine (Cymbalta) is detected in breast milk, though in relatively small amounts. According to the FDA drug label:

• Duloxetine is present in human milk with the peak concentration occurring approximately 3 hours after dosing 1
• The estimated infant dose is approximately 2 mcg/kg/day, which is less than 1% of the maternal dose 1
• There are reports of sedation, poor feeding, and poor weight gain in infants exposed to duloxetine through breast milk 1

Monitoring Recommendations

If a nursing mother requires duloxetine treatment:

• The infant should be closely monitored for:
  • Sedation
  • Poor feeding
  • Poor weight gain
  • Any changes in behavior 1

Risk-Benefit Assessment

The decision to use duloxetine while breastfeeding requires weighing:

1. The mother's need for treatment
2. The potential risks to the infant
3. The benefits of breastfeeding

The FDA label states: "The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for duloxetine delayed-release capsules and any potential adverse effects on the breastfed child from duloxetine delayed-release capsules or from the underlying maternal condition." 1

Clinical Evidence

Limited clinical evidence exists regarding duloxetine use during breastfeeding:

• One case report documented duloxetine use during pregnancy and breastfeeding with no evidence of developmental or other toxicity observed in the infant at birth or during the first 32 days after birth 2
• However, the possibility of functional or neurobehavioral effects appearing later cannot be excluded due to lack of long-term follow-up 2

Strategies to Minimize Infant Exposure

If duloxetine is deemed necessary during breastfeeding:

• Take medication immediately after breastfeeding to maximize clearance time before the next feeding
• Use the lowest effective dose for the shortest duration possible
• Consider timing feedings to avoid peak drug concentration in milk (approximately 3 hours after dosing) 1

Alternative Medications

For mothers requiring antidepressant treatment while breastfeeding, medications with more established safety profiles might be considered first, though this decision should be based on the mother's specific condition and treatment history.

Important Considerations

• Abrupt discontinuation of duloxetine can lead to withdrawal symptoms and should be avoided 1
• The risk of untreated maternal depression must be weighed against potential risks of medication exposure through breast milk
• Premature or otherwise compromised infants may be more susceptible to adverse effects and require additional monitoring

In conclusion, while duloxetine is not absolutely contraindicated during breastfeeding, careful consideration of risks and benefits along with close monitoring of the infant is essential if treatment is necessary.