Which term describes an agent that counteracts an unwanted drug effect?

Which term describes an agent that counteracts an unwanted drug effect?

• A. Reversal
• B. Countermeasure
• C. Antidote
• D. Antagonist

Answer: (C)

An antidote is an agent specifically used to counteract the toxic or harmful effects of a drug or toxin. This term directly describes something that neutralizes or reverses unwanted consequences, such as naloxone reversing opioid toxicity or acetylcysteine treating acetaminophen overdose. Reversal describes the act of negating a drug’s effect, often in a broader sense and sometimes used for specific agents that reverse pharmacologic action, but the standard label for a substance that counteracts toxicity is antidote. A countermeasure is a general term and not specific to drugs, and an antagonist is a receptor-blocking agent that prevents a drug’s effect at the receptor level; while an antagonist can counteract a drug’s effect, the most precise term for an agent that counteracts an unwanted drug effect is antidote.

An antidote is an agent specifically used to counteract the toxic or harmful effects of a drug or toxin. This term directly describes something that neutralizes or reverses unwanted consequences, such as naloxone reversing opioid toxicity or acetylcysteine treating acetaminophen overdose. Reversal describes the act of negating a drug’s effect, often in a broader sense and sometimes used for specific agents that reverse pharmacologic action, but the standard label for a substance that counteracts toxicity is antidote. A countermeasure is a general term and not specific to drugs, and an antagonist is a receptor-blocking agent that prevents a drug’s effect at the receptor level; while an antagonist can counteract a drug’s effect, the most precise term for an agent that counteracts an unwanted drug effect is antidote.