Lactation Failure in Postpartum Women Receiving a Dopamine Partial Agonist During Pregnancy

Background Third-generation antipsychotics like aripiprazole can suppress prolactin secretion via the tuberoinfundibular pathway, leading to postpartum lactation failure. This case series assesses the clinical management of this under-recognized postpartum complication in women with bipolar disorder (BD) maintained on long-acting injectables (LAIs) during pregnancy. Case Presentation We present three postpartum women (ages 26-31) with BD maintained on LAI aripiprazole who developed lactation failure. Each presented with reduced or absent milk production, and subphysiologic serum prolactin was documented (43-72 ng/mL). Management followed a stepwise algorithm: reducing the aripiprazole dose, initiating short-course metoclopramide where indicated, and/or augmentation/substitution to a prolactin-raising second-generation antipsychotic (SGA) such as risperidone (or quetiapine), alongside nonpharmacologic lactation support. Results Adequate lactation was restored within 1 month in all three patients, with normal prolactin values (298-320 ng/mL). In all cases, psychiatric stability was maintained without any manic relapse, and there were no reports of infant adverse effects. Conclusion Lactation failure due to the effects of dopamine partial agonists is not a random but rather predictable side effect. A structured approach combining aripiprazole dose reduction with targeted SGA augmentation or substitution can effectively restore breastfeeding capabilities while preserving maternal psychiatric stability. These findings require verification with more robust controlled trials.