Cal. Welfare and Institutions Code § 14195.3

(a) For purposes of the open drug formulary pilot project as established by this article, a provider may be reimbursed for any drug prescribed to a beneficiary if the drug is prescribed by a licensed provider within the scope of his or her practice, as defined by law, and if the drug is approved for use by the federal Food and Drug Administration. (b) Controlled substances shall be prescribed pursuant to the requirements of federal laws and regulations and the requirements set forth in Chapter 4 (commencing with Section 11150) of Division 10 of the Health and Safety Code. (c) For purposes of the open drug formulary pilot project as established by this article, there shall be no requirement that prior authorization be obtained by a provider before prescribing any drug to a beneficiary if the provider determines the drug to be a medical necessity in the treatment of the beneficiary. (d) For purposes of the open drug formulary pilot project as established by this article, a drug determined to be a medical necessity shall be one whose use in the treatment is reasonable and consistent with the objectives of the federal Medicaid Act as set forth in Title XIX of the Social Security Act (42 U.S.C. Sec. 1396 et seq.).