Which opioid should be avoided in patients with opioid dependence due to risk of withdrawal symptoms?

Which opioid should be avoided in patients with opioid dependence due to risk of withdrawal symptoms?

• A. Morphine
• B. Fentanyl
• C. Nalbuphine
• D. Codeine

Answer: (C)

Nalbuphine is a kappa agonist with mu receptor antagonism. In someone who is opioid-dependent, mu receptors are occupied by ongoing mu-agonist effect. Giving a mu antagonist like nalbuphine blocks or displaces that mu activity, triggering precipitated withdrawal symptoms. That’s why nalbuphine should be avoided in opioid-dependent patients. Pure mu agonists such as morphine or fentanyl continue to stimulate mu receptors and don’t precipitate withdrawal; codeine is a weaker mu agonist that doesn’t act as an antagonist.

Nalbuphine is a kappa agonist with mu receptor antagonism. In someone who is opioid-dependent, mu receptors are occupied by ongoing mu-agonist effect. Giving a mu antagonist like nalbuphine blocks or displaces that mu activity, triggering precipitated withdrawal symptoms. That’s why nalbuphine should be avoided in opioid-dependent patients. Pure mu agonists such as morphine or fentanyl continue to stimulate mu receptors and don’t precipitate withdrawal; codeine is a weaker mu agonist that doesn’t act as an antagonist.