Heroin overdose is usually treated with an opioid such as n

Heroin overdose is usually treated with an opioid _ such as naloxone (Narran) or naltrexone, an opioid, which prevents heroin from binding to mu receptors and reverses the effects of heroin on the body. antihistamine second messenger ligand agonist antagonist

Solution

      antagonist is the answer because the antagonist such as narcan has high affinity for opioid receptors.

antagonist means something that standsin opposition and here narcan can be used to counter the heroin .