Cal. Health and Safety Code § 111375

Any drug or device is misbranded unless its labeling bears all of the following information: (a) Adequate directions for use. (b) Such adequate warnings against use in pathological conditions or by children where its use may be dangerous to health. (c) Adequate warning against unsafe dosage or methods or duration of administration or application. Warnings shall be in a manner and form as are necessary for the protection of users. If the department determines that any requirement of subdivision (a), as applied to any drug or device, is not necessary for the protection of the public health, the department may adopt regulations exempting the drug or device from these requirements. Any drug or device exempted under Section 502(f) of the federal act (21 U.S.C. Sec. 352(f)) is exempt from the requirement of this section. The department, however, may adopt any regulation including a drug or device within, or excluding a drug or device from the requirements of this section, whether or not the inclusion or exclusion of the drug or device is in accord with the federal act.