Sertraline Safety During Breastfeeding
Sertraline is one of the safest antidepressants to use during breastfeeding, and women already taking it should be advised to continue the medication while breastfeeding. 1
Key Safety Data
The FDA label acknowledges that sertraline passes into breast milk and recommends discussing the best feeding approach with your healthcare provider, though it does not contraindicate breastfeeding 2. Research consistently demonstrates that infant exposure remains minimal:
- Infant exposure is extremely low, with daily infant dosage estimated at only 6.9 μg/kg after a 50 mg maternal dose, representing less than 1% (0.95%) of the weight-adjusted maternal dose 3
- Sertraline has the lowest relative infant dose among SSRIs, comparable only to fluvoxamine 4
- Sertraline and paroxetine are classified as first-line medications for postpartum depression in breastfeeding women based on safety index calculations 5
Practical Management Approach
Starting or Continuing Sertraline
- Begin with low doses and titrate slowly upward to the lowest effective dose 1
- Women already on effective sertraline treatment should continue rather than switch medications, as switching introduces unnecessary risks 1
- Monitor the newborn carefully for adverse effects, particularly in the first weeks 1
Infant Monitoring Requirements
Watch specifically for these signs in the breastfed infant:
- Irritability or agitation 1
- Poor feeding 1
- Uneasy or disrupted sleep 1
- Excessive sleepiness or decreased alertness 1
High-Risk Situations Requiring Extra Caution
Premature infants and low birth weight babies require heightened vigilance 1. One case report documented serotonergic overstimulation in a preterm infant, where limited metabolic capacity and immature blood-brain barrier led to therapeutic adult-range serum levels despite low milk intake 6. This represents an exceptional case but underscores the importance of careful monitoring in vulnerable infants.
Factors Affecting Infant Exposure
Maternal Genetics
- CYP2C19 poor metabolizers have 42% reduced sertraline clearance, potentially increasing both maternal plasma levels and milk concentrations 3
Breast Milk Composition
- Doubling milk fat content increases the milk-to-plasma ratio by 95% 3
- To minimize infant exposure when feasible, avoid breastfeeding at times of peak milk drug concentration 1
Evidence Quality Considerations
The safety profile is supported by multiple lines of evidence: a 2018 expert review in a drug safety journal 1, a 2024 population pharmacokinetic study 3, and a 2007 safety index analysis 5 all converge on sertraline's favorable risk-benefit profile. Only 3 adverse effects were reported among 119 breastfed infants across multiple studies 4, with the single serious case occurring in a premature infant with multiple risk factors 6.
The benefits of treating maternal depression and continuing breastfeeding outweigh the minimal risks of sertraline exposure in the vast majority of cases 4.