California Code, Business and Professions Code - BPC § 3661

A naturopathic doctor who uses the term or designation “Dr.” shall further identify themselves as “Naturopathic Doctor,” “Licensed Naturopathic Doctor,” “Doctor of Naturopathic Medicine,” or “Doctor of Naturopathy” and shall not use any term or designation that would tend to indicate the practice of medicine, other than naturopathic medicine, unless otherwise licensed as a physician and surgeon, osteopathic doctor, or doctor of chiropractic.