Section 7A. Upon obtaining or renewing a registration under section 7, a practitioner who prescribes controlled substances shall automatically and without further action be registered as a participant in the prescription monitoring program established in section 24A. The department shall provide each participant with a unique user name and access code for the program. For the purposes of this section, a practitioner shall not include a veterinarian; provided, however, that a practitioner shall include a physician assistant, nurse anesthetist or a registered nurse authorized by the board of registration in nursing to practice in an advanced practice nursing role.