California Code, Health and Safety Code - HSC § 11201

A prescription for a controlled substance, except those appearing in Schedule II, may be refilled without the prescriber's authorization if the prescriber is unavailable to authorize the refill and if, in the pharmacist's professional judgment, failure to refill the prescription might present an immediate hazard to the patient's health and welfare or might result in intense suffering.  The pharmacist shall refill only a reasonable amount sufficient to maintain the patient until the prescriber can be contacted.  The pharmacist shall note on the reverse side of the prescription the date and quantity of the refill and that the prescriber was not available and the basis for his judgment to refill the prescription without the prescriber's authorization.  The pharmacist shall inform the patient that the prescription was refilled without the prescriber's authorization, indicating that the prescriber was not available and that, in the pharmacist's professional judgment, failure to provide the drug might result in an immediate hazard to the patient's health and welfare or might result in intense suffering.  The pharmacist shall inform the prescriber within a reasonable period of time.  Prior to refilling a prescription pursuant to this section, the pharmacist shall make every reasonable effort to contact the prescriber.

The prescriber shall not incur any liability as the result of a refilling of a prescription pursuant to this section.