A. Coverage for medication approved by the federal food and drug administration that is prescribed for the treatment of a substance use disorder, pursuant to a medical necessity determination, shall not be subject to prior authorization, except in cases in which a generic version is available.

B. A health insurer shall not impose step therapy requirements before authorizing coverage for medication approved by the federal food and drug administration that is prescribed for the treatment of a substance use disorder, pursuant to a medical necessity determination, except in cases in which a generic version is available.