This opioid can be given via IV, IM, PO, SQ and has a 1-3 min onset that lasts for 4-6 hours; it is metabolized in the liver and excreted renally.

This opioid can be given via IV, IM, PO, SQ and has a 1-3 min onset that lasts for 4-6 hours; it is metabolized in the liver and excreted renally.

• A. Morphine sulfate
• B. Fentanyl
• C. Meperidine
• D. Hydromorphone

Answer: (A)

Morphine fits this pattern because it is easily given by IV, IM, subcutaneous, and oral routes, making it highly versatile for different clinical situations. When given by IV, its onset is very rapid—roughly 1 to 3 minutes—providing quick pain relief, and its effects usually last about 4 to 6 hours, which matches the duration described. Metabolically, morphine is processed in the liver into glucuronide metabolites, and these are cleared by the kidneys, so renal excretion is a key part of its elimination. This hepatic metabolism with renal excretion explains why dose adjustments may be needed in kidney disease and why certain metabolites can accumulate in renal impairment. Other opioids don’t fit as neatly. For instance, fentanyl is not typically used by mouth because of poor oral bioavailability and has a different duration profile, while meperidine has concerns about neurotoxic metabolites with renal impairment and a less predictable duration. Hydromorphone also works across several routes but its IV onset is not as rapid as morphine, so it doesn’t align as closely with the described 1–3 minute onset. So the combination of multiple routes, very rapid IV onset, a 4–6 hour duration, and the hepatic metabolism with renal excretion points to morphine as the best match.

Morphine fits this pattern because it is easily given by IV, IM, subcutaneous, and oral routes, making it highly versatile for different clinical situations. When given by IV, its onset is very rapid—roughly 1 to 3 minutes—providing quick pain relief, and its effects usually last about 4 to 6 hours, which matches the duration described. Metabolically, morphine is processed in the liver into glucuronide metabolites, and these are cleared by the kidneys, so renal excretion is a key part of its elimination. This hepatic metabolism with renal excretion explains why dose adjustments may be needed in kidney disease and why certain metabolites can accumulate in renal impairment.

Other opioids don’t fit as neatly. For instance, fentanyl is not typically used by mouth because of poor oral bioavailability and has a different duration profile, while meperidine has concerns about neurotoxic metabolites with renal impairment and a less predictable duration. Hydromorphone also works across several routes but its IV onset is not as rapid as morphine, so it doesn’t align as closely with the described 1–3 minute onset.

So the combination of multiple routes, very rapid IV onset, a 4–6 hour duration, and the hepatic metabolism with renal excretion points to morphine as the best match.