Final answer:
The medication used to reverse an opioid overdose is Narcan (naloxone). It acts quickly to restore breathing in an overdosed individual by blocking the effects of opioids on the receptors.
Step-by-step explanation:
The medication Narcan (naloxone) is used to reverse the effects of an opioid overdose. Opioids, which include drugs like heroin, morphine, and prescription painkillers such as oxycodone and fentanyl, can cause life-threatening respiratory depression. Naloxone works by antagonizing the actions of opioids at their receptors, quickly reversing the respiratory depression that leads to death during an overdose. While it has a short duration of action and must be administered parenterally, Narcan can provide vital minutes to keep the affected individual breathing until emergency medical treatment is available.
Epinephrine is used to treat anaphylactic shock, glucagon for low blood sugar, and albuterol for bronchospasm. These medications treat very different conditions and are not effective for opioid overdoses. The final answer to the question is A. Narcan (naloxone).