In this subchapter:
(1) "Emergency services personnel" includes firefighters, emergency medical services personnel as defined by Section 773.003, emergency room personnel, and other individuals who, in the course and scope of employment or as a volunteer, provide services for the benefit of the general public during emergency situations.
(2) "Opioid antagonist" means any drug that binds to opioid receptors and blocks or otherwise inhibits the effects of opioids acting on those receptors.
(3) "Opioid-related drug overdose" means a condition, evidenced by symptoms such as extreme physical illness, decreased level of consciousness, constriction of the pupils, respiratory depression, or coma, that a layperson would reasonably believe to be the result of the consumption or use of an opioid.
(4) "Prescriber" means a person authorized by law to prescribe an opioid antagonist.