What is the dosage of Naloxone (Narcan) for opioid overdose?

• A. 0.4 mg IV/IO
• B. 2 mg IV/IO, repeat every 3-5 minutes (maximum 8 mg)
• C. 1 mg IV/IM
• D. 0.04 mg IV/IO

Answer: (B)

Naloxone dosing is guided by titrating to reverse opioid-induced respiratory depression. Starting with a moderate, fast-acting dose and then repeating as needed helps restore breathing while avoiding overshoot effects. The recommended approach is to give 2 mg IV/IO, then repeat every 3–5 minutes if there’s not adequate improvement, with a maximum cumulative dose of 8 mg. This strategy provides rapid reversal and allows careful monitoring and adjustment, because the duration of naloxone is often shorter than that of long-acting opioids, so symptoms can return and additional dosing may be required. Lower fixed single doses (0.4 mg or 1 mg) or an extremely small dose (0.04 mg) may not reliably reverse unconscious patients or achieve prompt ventilation, and don’t guide ongoing titration.