Essential Reads: Breastfeeding and ADHD Medications

The use of stimulant medications for the treatment of attention-deficit/hyperactivity disorder (ADHD) by reproductive-age women is on the rise.  As a result, we are seeing more women in our clinic with questions about the reproductive safety of stimulants during pregnancy and the postpartum period.

We have a growing body of literature assessing the safety of stimulant medications during pregnancy; however, we have much less information on the use of stimulants during breastfeeding, and many women taking stimulants question whether it is safe to continue their medication while breastfeeding.

What Is the Indication for Treatment?

Stimulants are used frequently to treat ADHD, but the indications for their use vary widely. For women who are taking stimulants to treat narcolepsy or severe ADHD, withholding treatment may significantly affect the mother’s ability to function and may pose risks to the safety of both the mother and her infant. Similarly, some women use stimulants to augment the effects of antidepressants. Discontinuing the stimulant in this setting may increase vulnerability to postpartum depression. In these situations, we would consider continuing treatment with a stimulant while breastfeeding.

For women with milder forms of ADHD, we would more commonly recommend limiting the use of stimulants while breastfeeding. That said, there is growing recognition that untreated or inadequately treated ADHD may interfere with functioning during the postpartum period and may increase vulnerability to postpartum mood and anxiety symptoms. 

Treatment decisions should therefore be individualized, taking into account the severity of ADHD symptoms, the mother’s functional needs, and the potential risks and benefits of medication exposure through breast milk.

A recent review of ADHD during pregnancy and the postpartum period similarly emphasizes individualized treatment planning and notes that pharmacotherapy may be appropriate for women with moderate to severe ADHD. 

Data on Individual Stimulants

Methylphenidate

Data from 3 breastfeeding women taking methylphenidate (35–80 mg/day) suggest very low infant exposure, with an estimated relative infant dose (RID) of 0.7% or less. Methylphenidate was undetectable in the plasma of 3 breastfed infants. No adverse effects have been reported in breastfed infants exposed to methylphenidate, although the number of infants studied is small.

Amphetamine Salts

Data on amphetamine salts during breastfeeding are limited. In a case report of 1 woman taking amphetamine 35 mg/day, the estimated RID was 1.9%–2.1%, and no adverse effects were reported in the infant, who had normal growth and development. A 2024 pilot study followed 7 infants whose mothers were taking mixed amphetamine salts; these infants were part of a larger group of 13 children exposed to either mixed amphetamine salts or lisdexamfetamine during breastfeeding. No significant adverse effects or developmental concerns were identified.

Dextroamphetamine

In a study of 4 breastfeeding women taking dextroamphetamine (15–45 mg/day), the estimated RID was 5.7% (range 4%–10.6%). Dextroamphetamine was detectable in the plasma of 2 of 3 infants tested, at concentrations corresponding to 6% and 14% of maternal plasma concentrations. No adverse effects were reported in these 4 infants, who had normal growth and development.

Lisdexamfetamine

Lisdexamfetamine is a prodrug that is converted to dextroamphetamine. Therefore, available pharmacokinetic data reflect exposure to dextroamphetamine rather than lisdexamfetamine itself. In a prospective study of 6 women taking lisdexamfetamine, infants were exposed to low levels of amphetamine, with an estimated RID generally below 10%. Among the 13 infants whose mothers were taking either lisdexamfetamine or mixed amphetamine salts, 5 had possible adverse effects, including somnolence, crying or restlessness, colic, or constipation. All infants had normal developmental assessments. Importantly, these adverse events could not be attributed specifically to lisdexamfetamine because the study included both lisdexamfetamine and mixed amphetamine salts.

What Dose of Medication Is the Mother Using?

With any medication, the amount of drug that passes into breast milk—and therefore the amount to which the infant is exposed—is related to the mother’s dose. Higher doses of stimulants may result in greater infant exposure and could potentially increase the risk of adverse effects.

However, we do not have a clearly defined dose above which stimulant use should be avoided during breastfeeding. In the studies reported to date, doses have ranged from 15 to 80 mg/day for methylphenidate and approximately 20 to 35 mg/day for amphetamine preparations. In general, we recommend that women use the lowest effective dose and do not exceed the upper limit of the recommended dosage.

Impact of Stimulants on Milk Production

Both methylphenidate and amphetamines can reduce serum prolactin levels. Because prolactin plays an important role in the initiation of lactation, there has been concern that stimulant medications could interfere with milk production, particularly when lactation has not yet been established.

However, we have very limited data on whether reductions in prolactin actually translate into clinically meaningful reductions in milk production. Studies of dextroamphetamine in the early postpartum period have demonstrated reductions in serum prolactin, but did not measure milk production. In one case, a woman taking amphetamine 35 mg/day was able to exclusively breastfeed for 6 months without evidence of impaired milk production.

Similarly, no studies have demonstrated that methylphenidate reduces milk production. One woman who resumed methylphenidate while expressing breast milk had no meaningful change in her milk output.

Thus, while it is theoretically possible that stimulant-related suppression of prolactin could affect milk production, particularly early in lactation or at higher doses, there is currently no good evidence that therapeutic doses of stimulants consistently reduce milk supply. Women taking stimulants while breastfeeding should be attentive to milk production, particularly during the early postpartum period.

Immediate-Release versus Sustained-Release Preparations

Switching from a sustained-release to an immediate-release preparation may have some advantages for breastfeeding mothers because the dosing schedule can be modified to better accommodate the mother’s and baby’s sleep schedules. An immediate-release preparation may also allow the mother to adjust the timing of medication from day to day depending on her needs.

In theory, an immediate-release preparation may also allow a mother to minimize the infant’s exposure to medication. The amount of drug secreted into breast milk is related to the concentration of the drug in the mother’s blood. With immediate-release preparations, blood levels typically peak within 1–2 hours and then decline. With sustained-release preparations, blood levels rise more slowly and remain elevated for a longer period of time.

One approach to minimizing exposure would be to breastfeed or pump shortly before taking an immediate-release medication and, when practical, avoid breastfeeding during the period when maternal blood levels are highest. This approach is more feasible with immediate-release than sustained-release preparations. However, this strategy is not always necessary, particularly when the mother’s dose is low and infant exposure is already expected to be minimal.

How Old Is the Baby? Is the Baby Exclusively Breastfeeding?

The age and health of the infant are also important considerations. Preterm and newborn infants have reduced capacity to metabolize and eliminate medications than older infants and adults. Theoretically, this could make younger or medically fragile infants more vulnerable to medication exposure through breast milk.

In addition, infants who receive formula and/or solid foods are exposed to a smaller amount of breast milk—and therefore a smaller amount of medication—than infants who are exclusively breastfed.

Bottom Line

For women who require stimulant treatment during breastfeeding, the available data are generally reassuring. Methylphenidate appears to result in particularly low levels of infant exposure, with an RID of less than 1% and undetectable infant serum concentrations in the limited studies available. Amphetamine stimulants also appear in breast milk, but infant exposure is generally low, and reported adverse effects have been uncommon. Available developmental data, although limited, have been reassuring.

The decision to continue a stimulant during breastfeeding should be individualized. For women with severe ADHD or narcolepsy, the benefits of treatment may outweigh the potential risks of medication exposure through breast milk. For women with milder ADHD symptoms, reducing the dose or temporarily discontinuing medication may be reasonable. When treatment is continued, we generally recommend using the lowest effective dose.

When a mother is taking a stimulant while breastfeeding, we recommend monitoring the infant for symptoms such as irritability, excessive crying, poor sleep, or feeding difficulties, as well as monitoring normal growth and development. The available data are reassuring, but the number of infants studied remains small, and long-term neurodevelopmental data are limited. 

More research is needed to better understand the effects of stimulant exposure through breast milk, particularly with respect to long-term neurodevelopment and the potential effects of stimulant medications on milk production.