Is Zoloft (Sertraline) Safe for Breastfeeding Mothers?
Yes, sertraline (Zoloft) is one of the safest antidepressants for breastfeeding mothers and should be considered a first-line agent. 1, 2, 3, 4
Why Sertraline is Preferred
Sertraline and paroxetine are the preferred first-line antidepressants for breastfeeding mothers because they transfer into breast milk in the lowest concentrations and produce undetectable or very low infant plasma levels. 1
Sertraline consistently produces undetectable infant plasma levels in most cases, indicating minimal infant exposure even when present in breast milk. 1, 5
The American Academy of Family Physicians specifically recommends sertraline as one of the most commonly prescribed and safest antidepressants during breastfeeding. 1
Practical Dosing and Monitoring Strategy
Starting and titrating sertraline:
- Begin with low doses and slowly titrate upward to the lowest effective dose. 2
- The target should always be the minimum dose that achieves therapeutic benefit. 2
Infant monitoring is essential:
- Watch for irritability, poor feeding, uneasy sleep, or excessive crying—especially if the infant was born premature or had low birth weight. 1, 2
- Monitor for adequate weight gain and developmental milestones. 1
- Most reported adverse effects in infants are nonspecific and resolve spontaneously. 1
Timing of breastfeeding to minimize exposure:
- Breast milk sertraline levels are lowest 1 hour before ingestion and within 2 hours before to 1 hour after taking the medication. 5
- Peak milk concentrations occur 5-9 hours after ingestion. 5
- When feasible, breastfeed just before taking the medication or 1-2 hours before the next dose to minimize infant exposure. 2, 5
Safety Evidence
Low prevalence of adverse events:
- A retrospective cohort study found only a 12.5% prevalence rate of adverse events in infants exposed to sertraline or paroxetine, with most being mild. 6
- The most frequent adverse events were insomnia (88.9%), restlessness (55.6%), and constant crying (22.2%), all of which were mild and reversible. 6
Sertraline has a favorable safety index:
- Sertraline is classified as a first-line medication with a safety index value ≤2, indicating it should be relatively safe for use during breastfeeding. 4
- This contrasts with fluoxetine and citalopram, which produce higher infant plasma concentrations and have been associated with more frequent reports of suspected adverse effects. 1, 3, 4
Critical Decision Points
If already taking sertraline:
- Women already taking sertraline should be advised to breastfeed and continue the medication rather than discontinue either. 2
- The benefits of continued breastfeeding and maternal mental health treatment outweigh the minimal risks of sertraline exposure. 2
If considering switching to sertraline:
- Only switch from an ongoing and effective antidepressant after scrupulous evaluation of risks versus benefits. 2
- If the mother was successfully treated with another antidepressant during pregnancy, continuing that medication postpartum with careful infant monitoring may be preferable to switching. 3
If starting new treatment:
- Sertraline should be the first choice for initiating antidepressant treatment in breastfeeding mothers who wish to continue nursing. 1, 3, 4
FDA Label Considerations
- The FDA label states that "it is not known whether, and if so in what amount, sertraline or its metabolites are excreted in human milk" and recommends caution. 7
- However, this conservative FDA language is superseded by extensive clinical evidence and guideline recommendations supporting sertraline's safety profile in breastfeeding. 1, 2, 3, 4
Common Pitfall to Avoid
Do not advise discontinuation of breastfeeding when antidepressant treatment is indicated. 3 The fear of adverse events in the infant often leads mothers to avoid necessary treatment, but untreated maternal depression has severe repercussions on infant well-being that typically outweigh the minimal risks of sertraline exposure through breast milk. 4