(1) If any insurer authorized to transact the business of health insurance in this state reasonably determines that an insured’s utilization of prescription medications has been excessive and has not been medically necessary as defined by the insured’s coverage, the insurer may reserve the right to limit such insured to a pharmacy of the insured’s choice for obtaining prescription drug benefits. If the insured’s coverage is through a preferred provider organization, the insurer or preferred provider organization may limit the insured to a preferred provider pharmacy of the insured’s choice. If an insured has been so limited, the insurer or preferred provider organization shall not be required to provide benefits for prescriptions obtained from any other pharmacy. The insurer or preferred provider organization may require that the insured provide written notification to the insurer or preferred provider organization of the insured’s choice of pharmacy.

(2) The action by the insurer or preferred provider organization limiting an insured to one pharmacy of the insured’s choice may be effective as of the date specified in a written notice to the insured. Such written notice shall be sent to the insured at his or her last-known address as shown by the records of the insurer or preferred provider organization by certified or registered mail and shall inform the insured that he or she is required to select one pharmacy for obtaining prescription drug benefits. The terms of the written notice shall allow the insured at least seven days to notify the insurer or preferred provider organization of his or her choice of pharmacy.