Naloxone adult dose IM/IN

• A. 0.4-2 mg
• B. 0.2-0.4 mg
• C. 2-4 mg
• D. 4-8 mg

Answer: (A)

Naloxone works by quickly displacing opioid molecules from receptors, reversing the dangerous respiratory depression in opioid overdose. For an adult given by intramuscular or intranasal routes, start with a low but effective amount and build up only as needed. The typical initial adult IM dose is 0.4 mg, and you may repeat every 2–3 minutes if there’s no adequate improvement, up to a total of about 2 mg. This range (0.4–2 mg) covers both the starting dose and the common maximum that EMT-B protocols use before moving to further intervention or transport.

In intranasal use, this often translates to delivering about 0.4 mg per spray, with repeats as needed to reach roughly 2 mg total if symptoms persist. Higher single doses (like 2–4 mg or more) aren’t the standard starting point for EMT-B practice and carry a greater risk of withdrawal symptoms and adverse effects, so the practical dosing falls within 0.4–2 mg. If the patient improves, continue monitoring and provide supportive care; if symptoms return, re-dose as indicated and arrange transport.