For mild to moderate pain, which opioids are recommended?

• A. Methadone
• B. Butorphanol or Buprenorphine
• C. Morphine
• D. Fentanyl

Answer: (B)

For mild to moderate pain, you want an opioid that provides adequate relief without overdoing side effects like respiratory depression. Butorphanol is a kappa receptor agonist with mu receptor antagonism, giving analgesia with a safer respiratory profile and a relatively short duration that’s easy to titrate. Buprenorphine is a partial mu agonist with high receptor affinity and a long duration, offering reliable pain control with a ceiling effect on respiratory depression, which reduces overdose risk and makes it convenient for longer-lasting mild-to-moderate pain.

In contrast, morphine and fentanyl are full mu agonists that deliver stronger analgesia but carry higher risks of sedation and respiratory depression, which is less desirable for mild-to-moderate cases. Methadone is another potent mu agonist with NMDA antagonism and a long duration, typically used for specific chronic or more complex pain scenarios rather than straightforward mild-to-moderate pain.