Sec. 4. A policy of accident and sickness insurance may provide coverage for methadone if the drug is prescribed for the treatment of pain or pain management only as follows:
(1) If the daily dosage is not more than sixty (60) milligrams.
(2) If the daily dosage is more than sixty (60) milligrams, only if:
(A) prior authorization is obtained; and
(B) a determination of medical necessity has been shown by the provider.