California Business And Professions Code Section 13

The term materia medica as used in this code or in any initiative act referred to in this code, means those substances listed in the official United States Pharmacopoeia, the official Homeopathic Pharmacopoeia of the United States, the official United States Dispensatory, New and Nonofficial Remedies, or the National Formulary, or any supplement thereof, except substances covered by subdivision (a) of Section 4052 and Section 4057 of this code.