The following drugs are non-narcotic analgesics

Traditionally, analgesics can be divided into narcotic analgesics and non-narcotic analgesics. Narcotic analgesics are opioids, and non-narcotic analgesics include antipyretic analgesics, anti-anxiety analgesics and clonic analgesics. The above five drugs all act on opioid receptors and should belong to narcotic analgesics.

As for why the answer is pentazocine, it can be explained as follows:

Narcotic analgesics mainly refer to opioid receptors. At present, there are μ, γ and K receptors. The main pharmacological effects of opioids, such as analgesia, sedation, respiratory inhibition, pupil contraction, euphoria and dependence, are mainly mediated by μ receptors!

Pethidine, morphine, fentanyl and methadone are all opioid receptor agonists, which mainly act on μ opioid receptors and are addictive, so they belong to narcotic analgesics and belong to anesthetics in pharmaceutical administration!

On the other hand, pentazoxazine is a partial agonist of opioid receptors. Its analgesic effect is to stimulate opioid K receptor and antagonize opioid μ receptor, so it is less addictive. Pentazosin is classified as a non-narcotic drug in administration.

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