Notwithstanding any other law, a medical assistant may administer medication only by intradermal, subcutaneous, or intramuscular injections and perform skin tests and additional technical supportive services upon the specific authorization and supervision of a licensed physician and surgeon or a licensed podiatrist. A medical assistant may also perform all these tasks and services upon the specific authorization of a physician assistant, a nurse practitioner, or a certified nurse-midwife. The supervising physician and surgeon may, at his or her discretion, in consultation with the nurse practitioner, certified nurse-midwife, or physician assistant, provide written instructions to be followed by a medical assistant in the performance of tasks or supportive services.