Which statement about sufentanil onset is correct?

Which statement about sufentanil onset is correct?

• A. Onset of sufentanil is 1-3 minutes.
• B. Onset of sufentanil is 5-10 minutes.
• C. Onset of sufentanil is immediate.
• D. Onset of sufentanil is 15-20 minutes.

Answer: (A)

Sufentanil reaches effective brain concentrations very quickly after IV administration because it is extremely lipophilic, so it crosses the blood-brain barrier rapidly and activates mu receptors soon after bolus dosing. This results in analgesic effects that begin within about 1 to 3 minutes. Immediate onset would imply effect without any distribution time, which isn’t realistic given pharmacokinetics, and waiting 5–10 or 15–20 minutes would be much slower than expected for IV sufentanil. So the onset window of 1–3 minutes best fits its rapid, IV- onset profile.

Sufentanil reaches effective brain concentrations very quickly after IV administration because it is extremely lipophilic, so it crosses the blood-brain barrier rapidly and activates mu receptors soon after bolus dosing. This results in analgesic effects that begin within about 1 to 3 minutes. Immediate onset would imply effect without any distribution time, which isn’t realistic given pharmacokinetics, and waiting 5–10 or 15–20 minutes would be much slower than expected for IV sufentanil. So the onset window of 1–3 minutes best fits its rapid, IV- onset profile.