Summary of Use during Lactation

Preliminary information indicates that brexpiprazole in milk does not adversely affect infant growth and development, but that it might decrease the milk supply. Brexpiprazole has been used successfully to counteract galactorrhea and hyperprolactinemia in a woman taking paliperidone. If a mother requires brexpiprazole, it is not a reason to discontinue breastfeeding, but until more data are available, an alternate drug may be preferred. Monitor the infant for adequate weight gain.

Drug Levels

Maternal Levels. A woman with schizophrenia received brexpiprazole 2 mg once daily, risperidone 2 mg twice daily and quetiapine 12.5 mg twice daily during pregnancy and postpartum. Concentrations of brexpiprazole in breastmilk were 1 mcg/L on day 4 approximately 2 hours after the last dose, 2.3 mcg/L on day 5 at 6.5 hours after the last dose, and 6 mcg/L on day 6 at 22 hours after the last dose. The authors estimated the relative infant dose to be about 0.7%, although an insufficient amount of sampling was performed to verify this value.[1]

Infant Levels. A breastfed newborn infant whose mother was taking brexpiprazole 2 mg once daily, risperidone 2 mg twice daily and quetiapine 12.5 mg twice daily during pregnancy and postpartum had serum levels measured. At birth, the cord blood level was 3.9 mcg/L from maternal use during pregnancy. The neonate ingested small volumes of colostrum and milk 12 times from 46 to 86.5 hours after birth. Serum levels declined with a half-life of 45.9 hours between 16.5 and 41 hours after birth. By about 115 hours postpartum, brexpiprazole was undetectable (<0.5 mcg/L) in the infant’s serum.[1]

Effects in Breastfed Infants

Three mothers who took brexpiprazole 1 or 2 mg daily during pregnancy and postpartum delivered infants who partially breastfed. All had mild neonatal jaundice, which was thought to not be related to the drug. All infants were gaining weight and developing normally at one month of age and no adverse drug effects were reported.[2]

A woman with bipolar disorder took brexpiprazole and quetiapine during pregnancy and postpartum. The quetiapine dosage was titrated to 150 mg nightly, and the brexpiprazole dosage was 1 mg daily. The patient exclusively breastfed and her infant was closely monitored through 6 months of age. Growth parameters, physical health, and neurodevelopmental milestones were age appropriate, with no observed adverse effects attributable to medication exposure.[3]

Effects on Lactation and Breastmilk

A woman was taking brexpiprazole 2 mg daily during the third trimester of pregnancy for bipolar disorder. Her newborn infant was hospitalized in the NICU for hypoxic ischemic encephalopathy for 18 days. While her infant was in the NICU, she reduced her brexpiprazole dose to 2 mg every 2 days because of a shortage of medication. The mother, who had successfully breastfed 2 previous infants, pumped milk 10 times daily and was able to pump 120 mL daily by one week postpartum. After her infant was discharged, she increased the dose back to 2 mg daily. At a follow-up clinic visit, she could only pump 30 mL daily. She then stopped brexpiprazole and began a short course of metoclopramide. Within 10 days of stopping brexpiprazole, her milk supply increased, and she could almost exclusively breastfeed her infant who gained weight normally. Her serum prolactin level also increased to normal.[4]

A review of case reports of adverse reactions reported in the US Food and Drug Administration’s Adverse Event Reporting System from 2015 to 2023 found 6 reports of “lactation disorder” and 10 cases of “breast discharge” reported with brexpiprazole. Other details were lacking.[5]

Three mothers took brexpiprazole 1 or 2 mg daily during pregnancy and postpartum. All of them had to feed both formula and breastmilk, suggesting that the drug might suppress lactation. However, one of the infants was born with a cleft palate that made breastfeeding difficult.[2]

A 26-year-old woman with paranoid schizophrenia was started on paliperidone 12 mg daily. Twenty-six days after treatment initiation a satisfactory plasma paliperidone level of 42 mcg/L was achieved (therapeutic range 20 to 60 mcg/L). The patient developed galactorrhea 4 weeks following paliperidone initiation. Two serial prolactin measurements, weeks 4 and 5 weeks after treatment onset revealed persistent elevation of prolactin above the upper limit of normal, at 130 mcg/L (physiological range 5 to 23 mcg /L). Brexpiprazole 1 mg daily was begun to normalize serum prolactin. Three weeks after the introduction of brexpiprazole, a prolactin assay demonstrated a marked reduction in serum prolactin, from 130 to 37 mcg/L and the galactorrhea resolved. One month later the prolactin level remained at 39 mcg/L. The patient’s periods subsequently returned to a regular pattern also.[6]

Alternate Drugs to Consider

Haloperidol, Olanzapine, Quetiapine, Risperidone

References

1.

Konishi T, Kitahiro Y, Fujiwara N, et al. Pharmacokinetics of brexpiprazole, quetiapine, risperidone, and its active metabolite paliperidone in a postpartum woman and her baby. Ther Drug Monit 2024;46:687–91. [PubMed: 38648649]

2.

Fukuda A, Oyanagi G, Kikuchi S, et al. Evaluation of the safety of taking brexpiprazole during the lactation period. Breastfeed Med 2026;21:275–9. [PubMed: 41649070]

3.

Alsupiany A. Brexpiprazole and quetiapine use during pregnancy and lactation: A case report. Clin Case Rep 2026;14:e73092. [PMC free article: PMC13337537] [PubMed: 42416040]

4.

Berlin S, Bodnar K. Low breast milk production associated with brexipiprazole (Rexulti). Breastfeed Med 2020;15:A–3. doi:10.1089/bfm.2020.29162.abstracts [CrossRef]

5.

Jiang Y, Zhou L, Shen Y, et al. Safety assessment of brexpiprazole: Real-world adverse event analysis from the FAERS database. J Affect Disord 2024;346:223–9. [PubMed: 37956832]

6.

Humbert-Claude M, Barbé T, Ionescu MC, et al. Brexpiprazole mitigates hyperprolactinaemia induced by paliperidone in a patient with a history of skin reaction to aripiprazole: Case report introducing a new therapeutic approach. BJPsych Open 2026;12:e137. [PMC free article: PMC13184606] [PubMed: 42144793]

Substance Name

Brexpiprazole

CAS Registry Number

913611-97-9

Drug Class

Breast Feeding

Lactation

Milk, Human

Antipsychotic Agents

Serotonin Agents

Dopamine Agonists