Inappropriate lactation--that which occurs beyond the usual postpartum or breast-feeding period or in the male--has been of medical interest for centuries. There is a suggestion that the first recorded case occurred in the Bible in the Book of Esther wherein Mordecai may have breast-fed his niece Esther [1,2]. The Talmud describes a man who nursed his infant after his wife's death during childbirth [3]. Lactation in virgin women was noted by the early Greeks [4], and Aristotle observed lactation in men [5]. The phenomenon of "witch's milk," seen in the newborn, was described as early as 1684 by Bonetus [6]. The first alleged pediatric case of nonpuerperal lactation was of an 8-year-old girl who was able to suckle her baby brother as reported in the 18th Century by Baudelocque [7]. Subsequently, many other cases of abnormal lactation were described in the 19th and early 20th centuries [7-10]. In the past 15 years, there has been a vast proliferation of cases and studies concerning galactorrhea of both sexes [11]. The advent of the prolactin radioimmunoassay was the single most important factor behind the profusion of these investigations [11-14]. Most recently, attention has focused on the high incidence of pituitary tumors--specifically the prolactinoma--in women and to some degree in men [13,15]. The occurrence of such tumors in children and adolescents is also receiving more attention [16,17]. The purpose of this review is to update the reader on galactorrhea with a specific emphasis on: 1) outlining the various causes of galactorrhea that may be seen in adolescent patients; 2) describing the work-up and management of both the male and female adolescent patient with galactorrhea; and 3) describing what is known about the natural history of galactorrhea. A brief description of the physiology of the hypothalamic-pituitary-breast axis and lactation is also presented.