Metoclopramide Increases Prolactin Release and Milk Secretion in Puerperium without Stimulating the Secretion of Thyrotropin and Thyroid Hormones*

Publisher Website
Google Scholar
Abstract
To explore the effect of metoclopramide (MC) on the secretion of PRL [prolactin], TSH [thyrotropin], and thyroid hormones (T3 [triiodothyronine] and T4 [thyroxine]) and on defective lactation, 17 mothers with poor lactation were treated with oral MC (10 mg, 3 times daily) for 3 wk starting 18-141 days postpartum. After a pause of 1 wk, the medication was given for a further 2 wk. The breast milk yield was monitored objectively before and during the trail. Stimulation tests [i.v.] with MC (10 mg) and TRH [thyrotropin releasing hormone] (200 .mu.g) were done before and at the end of oral MC therapies. Oral MC increased the mean (.+-. SEM [standard error of the mean]) plasma PRL level from 36.6 .+-. 9.2 to 90.6 .+-. 7.5 ng/ml (P < 0.001) after 1 wk, and the PRL level remained elevated for as long as MC was administered. During the pause, the PRL level decreased to 19.5 .+-. 7.5 ng/ml, but increased once again during the 2nd MC treatment to 85.5 .+-. 16.0 ng/ml (P < 0.01). Plasma TSH, T3 and T4 did not change. The PRL level rose significantly after TRH and MC injections before and during oral treatments with MC, the TSH concentrations were elevated only after TRH stimulation. The PRL response to i.v. MC or TRH and the TSH response to i.v. TRH were not affected by oral MC treatment. The mean daily milk volume increased from 433 .+-. 55 to 626 .+-. 76 ml (P < 0.001) during the 1st treatment and from 390 .+-. 73 to 606 .+-. 56 ml (P < 0.01) during the 2nd oral MC treatment. Correspondingly, the volume of daily supplemental alimentation decreased from 348 .+-. 61 to 280 .+-. 59 ml (P < 0.05) and from 526 .+-. 68 to 363 .+-. 66 ml (P < 0.01), respectively. MC caused no significant side effects.

This publication has 19 references indexed in Scilit: