Short-term increase of sperm output under metoclopramide administration

Nine volunteers were treated with metoclopramide (10 mg T.D.S.) for 4 weeks. Prolactin levels rose both in serum and in seminal plasma 1 week following the initiation of metoclopramide administration. At this point in time, sperm density and total sperm count increased about twofold. Thereafter, levels of prolactin slowly decreased while sperm density and total sperm count fell back to initial values.