The Choice You Should Not Have to Make

You are struggling. Maybe it is postpartum depression, the kind where getting through each day feels like wading through wet concrete. Maybe it is anxiety so intense that you cannot sleep even when the baby sleeps. Maybe intrusive thoughts have taken up residence in your mind and will not leave.

You need help. Your provider has recommended medication. And then someone says: "But you are breastfeeding."

Suddenly you feel trapped. Your mental health on one side, your baby's feeding on the other, and the implicit message that choosing medication means you are choosing yourself over your child.

This is one of the most harmful false dichotomies in postpartum care. And it is largely based on outdated information.

The Reality: Many Medications Are Compatible with Breastfeeding

Here is what perinatal psychiatrists and lactation researchers want you to know: the majority of commonly prescribed psychiatric medications are considered compatible with breastfeeding. Not risk-free (no medication is, including over-the-counter drugs), but compatible, meaning the benefits of treatment typically outweigh the small amount of medication that transfers into breast milk.

The amount of most psychiatric medications that actually reaches a breastfed infant is remarkably small. For many medications, the infant receives less than 10% of the weight-adjusted maternal dose through breast milk, and often much less. The infant's own metabolism further reduces exposure.

This does not mean every medication is equally safe during breastfeeding. But it does mean the conversation should start from a place of "most options are on the table" rather than "you have to stop breastfeeding."

How Medication Safety in Breastfeeding Is Evaluated

Several factors determine how much of a medication reaches a breastfed infant and what effects it might have:

Relative Infant Dose (RID)

This is the standard measure of infant exposure through breast milk. It calculates the dose the infant receives as a percentage of the mother's weight-adjusted dose. Generally:

  • RID below 10% is considered acceptable for most medications
  • Many psychiatric medications have RIDs well below this threshold

Protein Binding

Medications that are highly bound to proteins in the blood tend to stay in the blood rather than transferring into breast milk. Many SSRIs, for example, are highly protein-bound.

Molecular Weight and Lipophilicity

Larger molecules have more difficulty crossing into breast milk. Medications that are highly fat-soluble may concentrate in breast milk to some degree, but this is just one factor among many.

Infant Age and Health

Premature infants or those with liver or kidney conditions may metabolize medications differently than healthy, term infants. The age of the infant matters too: a newborn's ability to metabolize medications is more limited than a six-month-old's.

Oral Bioavailability

Some medications that enter breast milk are poorly absorbed from the infant's gastrointestinal tract, further reducing actual exposure.

LactMed: The Gold Standard Resource

If you want to research a specific medication's compatibility with breastfeeding, the best resource available is LactMed, a database maintained by the National Library of Medicine (part of the National Institutes of Health).

LactMed provides:

  • Detailed summaries of published research on each medication's transfer into breast milk
  • Reported effects on breastfed infants
  • The relative infant dose when available
  • Alternative medications to consider
  • References to the primary research

LactMed is free, publicly accessible, and regularly updated. It is the same resource that perinatal psychiatrists, lactation consultants, and pharmacists use. You can find it at toxnet.nlm.nih.gov (search for "LactMed") or through the NIH website.

Another valuable resource is the InfantRisk Center, founded by Dr. Thomas Hale (author of the reference text "Medications and Mothers' Milk"), which offers a helpline and app for medication safety questions during breastfeeding.

Specific Medication Classes: What the Evidence Shows

SSRIs

  • Sertraline (Zoloft): Often considered the first-line choice for breastfeeding parents. Very low levels in breast milk. The relative infant dose is typically well below 5%. Multiple studies have found no adverse effects in breastfed infants.
  • Paroxetine (Paxil): Also has very low breast milk transfer. However, it is less commonly prescribed due to its shorter half-life and potential for discontinuation symptoms.
  • Fluoxetine (Prozac): Slightly higher breast milk levels than sertraline, and its active metabolite has a long half-life. Some reports of infant irritability. Often not the first choice during breastfeeding, but still used when it is the most effective medication for the parent.
  • Escitalopram (Lexapro) and citalopram (Celexa): Low to moderate breast milk levels. Generally considered compatible with breastfeeding with monitoring.

SNRIs

  • Venlafaxine (Effexor): Moderate breast milk levels, but the amount reaching the infant is still typically below the 10% RID threshold. Compatible with breastfeeding for most families.
  • Duloxetine (Cymbalta): Limited but reassuring data. Low relative infant dose.

Mood Stabilizers

  • Lamotrigine (Lamictal): Does transfer into breast milk at meaningful levels, and infant blood levels can be measurable. However, lamotrigine has been used during breastfeeding with monitoring, and serious adverse effects are uncommon. A perinatal psychiatrist can help weigh the benefits against the higher-than-average exposure.
  • Lithium: Transfers into breast milk and requires infant monitoring (blood levels, thyroid, and kidney function). Not universally recommended during breastfeeding, but can be appropriate for severe bipolar disorder when the alternative is no treatment or less effective treatment.

Benzodiazepines

  • Generally used cautiously during breastfeeding. Shorter-acting formulations (lorazepam) at low doses are preferred over longer-acting ones (diazepam).
  • Occasional use is typically well-tolerated. Regular use requires monitoring for infant sedation.

Antipsychotics

  • Quetiapine (Seroquel): Very low breast milk transfer. Generally considered compatible.
  • Olanzapine (Zyprexa): Low breast milk levels. Compatible with monitoring.
  • Aripiprazole (Abilify): Limited data but appears to have low transfer. Used during breastfeeding when indicated.

The Risk of Not Treating

This is the part of the conversation that is too often overlooked. When we talk about the "risk" of medication during breastfeeding, we must also talk about the risk of leaving a postpartum mental health condition untreated.

Untreated postpartum depression and anxiety can affect:

  • The parent-infant bond. Research consistently shows that postpartum depression can impair the responsiveness, warmth, and engagement that infants need for healthy attachment.
  • Infant development. Children of parents with untreated postpartum depression are at higher risk for cognitive, emotional, and behavioral difficulties.
  • Breastfeeding itself. Ironically, untreated depression and anxiety are among the most common reasons people stop breastfeeding earlier than they intended. Pain, difficulty with latch, and low supply can all be worsened by the stress response that accompanies untreated mental illness.
  • Family functioning. Untreated parental mental illness affects partners, older children, and the family system as a whole.
  • Parental safety. In severe cases, untreated postpartum mental illness can lead to self-harm or suicidal ideation. Maternal suicide is a leading cause of postpartum mortality.

A parent who is well enough to be present, responsive, and engaged with their baby is providing something more important than any specific feeding method.

Shared Decision-Making: How It Should Work

The decision about medication during breastfeeding should be a collaborative process between you and your provider (ideally a perinatal psychiatrist or a prescriber with perinatal expertise). Here is what that process should look like:

1. Your provider presents the evidence about your specific medication (or potential medications), including what is known about breast milk transfer, infant effects, and alternatives.

2. You share your values and priorities. How important is breastfeeding to you? What are your concerns about medication? What are your symptoms and how are they affecting your daily life and your baby?

3. Together, you weigh the options. These might include: continuing your current medication and breastfeeding, switching to a medication with more breastfeeding data, starting medication at a lower dose and monitoring, or exploring non-medication treatments first (therapy, support groups, lifestyle interventions) with medication as a backup plan.

4. The decision is yours. Your provider gives you information and a recommendation. You make the final call. Both choices, medication or no medication, breastfeeding or formula, are valid.

What Shared Decision-Making Is Not

  • Being told "you have to stop breastfeeding" without discussion of compatible medications
  • Being told "you should just push through" without being offered treatment
  • Being made to feel guilty for either choosing medication or choosing to avoid it
  • Having the decision made for you by anyone other than you

When to Seek a Perinatal Psychiatrist Specifically

If you are taking or considering psychiatric medication while breastfeeding, a perinatal psychiatrist offers the most specialized guidance. Consider seeking one if:

  • Your OB or primary care provider is not comfortable prescribing psychiatric medication during breastfeeding
  • You are on multiple medications and need a specialist to evaluate the combined risk
  • You have a complex psychiatric history (bipolar disorder, psychotic features, treatment-resistant depression)
  • You want a thorough, evidence-based discussion about your options rather than a blanket "stop breastfeeding" or "stop medication" recommendation
  • Your current provider's advice conflicts with what you are finding in evidence-based resources like LactMed

You Are Not Choosing Between Your Baby and Yourself

The framing of "medication versus breastfeeding" creates a false conflict. In reality, a parent who is mentally well is giving their baby something irreplaceable, regardless of how that baby is fed. And in most cases, medication and breastfeeding can coexist safely.

You deserve accurate information, compassionate support, and the freedom to make the choice that is right for your family.

If you are looking for a perinatal psychiatrist or postpartum mental health support, BAABY can help you find providers who specialize in exactly this kind of care.