Bus. & Prof. Code, § 2239

(a) The use or prescribing for or administering to himself or herself, of any controlled substance; or the use of any of the dangerous drugs specified in Section 4022, or of alcoholic beverages, to the extent, or in such a manner as to be dangerous or injurious to the licensee, or to any other person or to the public, or to the extent that such use impairs the ability of the licensee to practice medicine safely or more than one misdemeanor or any felony involving the use, consumption, or self-administration of any of the substances referred to in this section, or any combination thereof, constitutes unprofessional conduct. The record of the conviction is conclusive evidence of such unprofessional conduct.

(b) A plea or verdict of guilty or a conviction following a plea of nolo contendere is deemed to be a conviction within the meaning of this section. The Division of Medical Quality may order discipline of the licensee in accordance with Section 2227 or the Division of Licensing may order the denial of the license when the time for appeal has elapsed or the judgment of conviction has been affirmed on appeal or when an order granting probation is made suspending imposition of sentence, irrespective of a subsequent order under the provisions of Section 1203.4 of the Penal Code allowing such person to withdraw his or her plea of guilty and to enter a plea of not guilty, or setting aside the verdict of guilty, or dismissing the accusation, complaint, information, or indictment.