John R. Brinkley was born on July 8, 1885 in Jackson County, North Carolina. He grew up in that area and attended medical schools in Chicago and Kansas City, Missouri, before setting up a medical practice in Milford, Kansas in 1917. He had received a degree from the Kansas City Eclectic Medical University on May 7, 1915. Brinkley took the Arkansas state medical board examination and received a license to practice in Kansas because of a reciprocity agreement between the two states. In addition to his medical practice, Brinkley operated a drugstore stocked with patent medicines. Shortly after moving to Milford, Brinkley reportedly transplanted a goat testicle into a human. The operation, aimed at sexual rejuvenation, was declared a success and gained Brinkley his "goat gland doctor" reputation.