Sec. 353.003. EFFECT OF CHAPTER. This chapter does not prevent or restrict a physician from: (1) treating or prescribing for a patient; or (2) directing or instructing a person under the physician's control or supervision who assists a patient according to a specific direction, order, instruction, or prescription. Acts 1999, 76th Leg., ch. 388, Sec. 1, eff. Sept. 1, 1999.