Safety of Duloxetine (Cymbalta) During Pregnancy
Duloxetine use during pregnancy should be avoided when possible due to potential risks to the fetus, including decreased fetal weight, increased risk of postpartum hemorrhage, and potential neonatal complications requiring prolonged hospitalization. 1
Risks of Duloxetine in Pregnancy
Fetal and Neonatal Risks
- Animal studies show decreased fetal weights at therapeutic doses, though no evidence of developmental effects or malformations at doses up to 3-6 times the maximum recommended human dose 1
- Neonates exposed to duloxetine and other SNRIs/SSRIs late in the third trimester have developed complications requiring:
- Prolonged hospitalization
- Respiratory support
- Tube feeding 1
- These complications can arise immediately upon delivery and may include:
- Respiratory distress
- Cyanosis
- Apnea
- Seizures
- Temperature instability
- Feeding difficulties
- Vomiting
- Hypoglycemia
- Hypotonia/hypertonia
- Tremor and irritability 1
Maternal Risks
- Use of duloxetine in the month before delivery may be associated with an increased risk of postpartum hemorrhage 1
- Limited data from a postmarketing retrospective cohort study did not identify a clear drug-associated risk of major birth defects 1, 2
- Increased risk of spontaneous abortion has been reported 2, 3
Breastfeeding Considerations
- Duloxetine is present in breast milk, with approximately 7 mcg/day transferred while on a 40mg twice daily dose 1
- The estimated daily infant dose is approximately 2 mcg/kg/day, less than 1% of the maternal dose 1
- Infants should be monitored for:
- Sedation
- Poor feeding
- Poor weight gain 1
- Infant exposure to duloxetine in breast milk is less than 1% of the maternal weight-adjusted dose, suggesting relative safety during breastfeeding 3
Risk-Benefit Assessment
Risks of Untreated Depression
- Women who discontinue antidepressants during pregnancy are more likely to experience relapse of major depression 1
- Untreated depression during pregnancy is associated with:
- Premature birth
- Decreased initiation of breastfeeding 4
Clinical Decision Making
- Consider the severity of the maternal depression
- Evaluate alternative treatment options with better established safety profiles
- If duloxetine must be continued:
- Use the lowest effective dose
- Consider discontinuation or dose reduction before delivery if clinically appropriate
- Monitor the neonate closely after birth for complications
Monitoring Recommendations
For pregnant women taking duloxetine:
- Regular prenatal care with attention to fetal growth
- Consider tapering dose before delivery when clinically appropriate
- Prepare neonatal team for potential complications
For breastfeeding women:
- Monitor infant for sedation, poor feeding, and poor weight gain
- Consider timing breastfeeding to avoid peak maternal drug concentrations
Alternative Options
- For depression during pregnancy, medications with more extensive safety data (such as certain SSRIs) might be preferable
- Non-pharmacological approaches like psychotherapy should be considered as adjunctive or alternative treatment when appropriate
While the available data on duloxetine use in pregnancy is limited, the potential risks to the fetus and neonate must be carefully weighed against the risks of untreated maternal depression when making treatment decisions.