Which of the following is NOT an opiate: Codeine, Diazepam (Valium), Morphine, or Oxycodone?

Diazepam (Valium) is NOT an Opiate

Diazepam (Valium) is the only medication in the list that is NOT an opiate - it is a benzodiazepine. 1

Classification of the Listed Medications

Opiates/Opioids

1. Codeine - An opiate classified as a WHO level II analgesic (moderate pain) 1

   • Natural opiate derived from the opium poppy
   • Used for moderate pain, often in combination with acetaminophen/paracetamol
   • Metabolized to morphine through CYP2D6 enzyme 1

2. Morphine - A pure opioid agonist used for severe pain 1

   • Considered the gold standard strong opioid (WHO level III analgesic)
   • Available in multiple formulations (oral, parenteral, rectal)
   • Most commonly used opioid for cancer pain management

3. Oxycodone - A pure opioid agonist used for moderate to severe pain 1

   • Strong opioid (WHO level III analgesic)
   • Available in immediate and extended-release formulations
   • Approximately 2/3 to 3/4 as potent as morphine when administered parenterally 2

Benzodiazepine

1. Diazepam (Valium) - A benzodiazepine, NOT an opiate 1, 3
   • Acts on GABA receptors in the central nervous system
   • Used primarily as an anxiolytic, muscle relaxant, and anticonvulsant
   • Often co-prescribed with opioids, which can increase risk of respiratory depression 3

Evidence-Based Differentiation

The classification of these medications is clearly established in medical guidelines. According to the American Academy of Pediatrics guideline on neonatal drug withdrawal, diazepam is categorized as a benzodiazepine under CNS depressants, while morphine, codeine, and oxycodone are all listed under opioids 1.

This classification is further supported by the World Journal of Emergency Surgery guidelines on postoperative pain management, which discusses opioids (including morphine, oxycodone, and fentanyl) as a distinct class of medications from benzodiazepines 1.

Clinical Implications

The distinction between opiates and benzodiazepines is clinically significant for several reasons:

• Different mechanisms of action: Opiates act primarily on μ-opioid receptors, while benzodiazepines enhance the effect of GABA at the GABA-A receptor
• Different indications: Opiates are primarily used for pain management, while benzodiazepines are used for anxiety, muscle relaxation, and seizure control
• Combined risk: When opiates and benzodiazepines are used together, there is an increased risk of respiratory depression and fatal overdose 3

Common Pitfalls

• Confusing benzodiazepines with opiates can lead to inappropriate prescribing and dangerous drug interactions
• Both medication classes can cause dependence and withdrawal, but through different mechanisms
• The combination of opiates and benzodiazepines significantly increases the risk of respiratory depression and overdose death

Understanding the fundamental differences between these drug classes is essential for safe prescribing practices and appropriate pain management.