Objective: Mothers of many preterm babies are unable to produce sufficient milk for their babies during the prolonged hospitalization. Domperidone stimulates the release of prolactin, thereby increasing breast milk production. The primary outcome was to study the efficacy of domperidone in augmenting breast milk production in mothers with lactation failure (LF). The secondary outcomes included the effect of domperidone on prolactin levels, adverse effects of domperidone, and outcome on breastfeeding rates at discharge. Materials and Methods: This was a randomized, double-blinded, placebo-controlled trial where mothers with LF were either allocated domperidone (10 mg) or placebo, 2 tablets three times a day for 14 days. Milk volumes were recorded daily for 14 days. Serum prolactin levels were measured at the start and at day 7 of study. Results: Out of 166 women eligible for the study, 119 (71.7%) mothers were able to increase their breast milk production without pharmacological treatment after being counseled on the advantages of human milk and proper breastfeeding management. Forty-seven mothers were finally enrolled in the study; 24 in the domperidone group (DG) and 23 in the placebo group (PG). Breast milk production increased from a baseline of 156 + 141.1 to 400.9 + 239.2 mL in the DG and increased from a baseline of 175.8 + 150.7 to 260.5 + 237.5 mL in the PG, after 14 days (p < 0.01). The prolactin levels in the DG and PG increased from 72.85 (22.2-167.15) and 42.33 (14.02-93.54) ng/mL, respectively, to 223.4 (49.79-280.2) ng/mL (p = 0.005) in the DG and 60.08 (14.31-132.14) ng/mL (p = 0.232) in the PG on the 7th day of treatment. No adverse effects were recorded. Ninety-five percent of babies in the DG were exclusively breastfeeding at hospital discharge, compared with 52.4% in the PG (p = 0.008). Conclusion: Domperidone treatment can result in an increase in breast milk production with no adverse effects. The study was registered with the Thai Clinical Trials Registry ID TCTR2020091008.
Keywords: domperidone; lactation failure; milk production; prematurity.