A Delaware County mental health counselor accused of getting prescription drugs from his clients has voluntarily surrendered his medical license. 41-year-old Mark Davison of Manchester gave up his license under an agreement with the Iowa Board of Psychological Examiners. He was ordered to undergo a physical and mental evaluation in June. The board says he failed to satisfy the conditions and terms of the order. Davison worked for the Regional Medical Center in Manchester. He was arrested in May and charged with two criminal complaints for 15 a total of counts related to using his patients to get drugs for himself.