Which of the following ranges is a common initial naloxone dose for suspected opioid overdose?

• A. 0.4-2 mg
• B. 20-40 mg
• C. 0.04-0.2 mg
• D. 4-6 mg

Answer: (A)

Naloxone is used to quickly reverse opioid-induced respiratory depression by competing with opioids at the receptors. The safe and effective approach is to start with a small, titratable dose and reassess the patient’s breathing and mental status, increasing the dose only as needed.

The common initial dose range of 0.4 to 2 mg is chosen because it often reverses respiratory depression promptly without causing unnecessary withdrawal or severe sympathetic effects. By giving a small dose first and watching the response, you can restore adequate ventilation and then add more if needed in 0.4–1 mg increments every 2–3 minutes until breathing improves.

Doses much lower, like 0.04–0.2 mg, are generally inadequate to reverse significant opioid overdose. Very high initial doses, such as 4–6 mg or 20–40 mg, are not typical as starting points and can increase the risk of withdrawal, agitation, hypertension, and other complications.