Long-acting injectable naltrexone shall be approved as part of a prior authorization process by any Medicaid managed care plan operating under contract with the Commonwealth for eligible offenders enrolled in the pilot program and receiving comprehensive substance abuse treatment which includes the monitoring of medication adherence upon their release from county correctional institutions. Within 90 days of the effective date of this section, the Department of Human Services shall issue a bulletin notice to instruct Medicaid managed care plans that approval for the use of long-acting injectable naltrexone must be granted if the eligible offenders are enrolled in the pilot program upon their release from county correctional institutions.