22 Tex. Admin. Code § 169.4
Except as otherwise provided in § 169.5 of this chapter, a physician may provide, dispense, or distribute drugs for use or consumption by the patient away from the physician's office or after the conclusion of the physician-patient encounter only in quantities as are necessary to meet the patient's immediate needs. A physician shall comply personally with all appropriate labeling and record keeping requirements under state or federal law or shall oversee compliance by persons acting under his or her direction and supervision. A physician who provides, dispenses, or distributes drugs to a patient to meet his or her immediate needs may not charge a fee separate from that charged for medical services provided to the patient.
22 Tex. Admin. Code § 169.4