Which analgesic is contraindicated in sickle cell crisis?

• A. Morphine
• B. Hydromorphone
• C. Meperidine (Demerol)
• D. Fentanyl

Answer: (C)

Meperidine is contraindicated in a sickle cell crisis because its metabolite, normeperidine, can accumulate and cause CNS toxicity, including tremors and seizures, especially during acute pain episodes when hydration and renal function may be stressed. This neurotoxic potential makes it unsafe for vaso-occlusive crises. In contrast, morphine, hydromorphone, and fentanyl provide effective analgesia without this risk from toxic metabolites, making them preferred choices for managing acute pain in sickle cell crises. Always monitor for respiratory depression with any opioid, but the unique metabolite issue is why meperidine is avoided here.