Which drug classification counteracts poisons and their effects (Narcan)?

• A. Antihistamine
• B. Antibiotic
• C. Antivenom
• D. Antidote

Answer: (D)

Antidotes are substances that counteract poisons and their effects. Naloxone (Narcan) is a classic example: it binds to opioid receptors in place of opioids, quickly reversing danger from an opioid overdose and restoring normal breathing. This makes it a direct antidote for opioid toxicity.

The other options don’t fit this broad role. Antihistamines block histamine to treat allergy symptoms, not poisoning. Antibiotics treat bacterial infections, not toxins. Antivenoms neutralize venom from bites or stings, which is a specific toxin exposure, not poisons in general.