What is the common IV dose of fentanyl used for analgesia in the ED, and how is it typically administered?

• A. 25–50 mcg IV
• B. 10–25 mcg IV
• C. 50–100 mcg IV; may repeat
• D. 100–150 mcg IV

Answer: (C)

Fentanyl used in the ED for rapid analgesia is given as IV bolus doses that you titrate to the patient’s response. The usual starting range is fifty to one hundred micrograms given IV, and you can repeat dosing every few minutes (commonly every five to ten minutes) until adequate analgesia is achieved, with careful monitoring for respiratory depression and sedation. This approach leverages fentanyl’s quick onset and short duration, allowing precise control of pain relief while minimizing prolonged effects. Smaller doses, like ten to twenty-five micrograms, are typically not sufficient for analgesia in most ED patients, and higher single doses (hundred to one hundred fifty micrograms) are less common as the initial standard due to greater risk of adverse effects.