Sec. 8. (a) For substitution to occur for a prescription other than a prescription filled under the Medicaid program (42 U.S.C. 1396 et seq.), the children's health insurance program established under IC 12-17.6-2, the biosimilar biological products requirements under IC 16-42-25, or the Medicare program (42 U.S.C. 1395 et seq.):
(1) the practitioner must:
(A) sign on the line under which the words "May substitute" appear; or
(B) for an electronically transmitted prescription, electronically transmit the instruction "May substitute."; and
(2) the pharmacist must inform the customer of the substitution.
(b) This section does not authorize any substitution other than substitution of a generically equivalent drug product.