Opioid Use Disorder & Overdose

The triad of pinpoint pupils, respiratory depression, and unresponsiveness tells you the clock is ticking — naloxone reversal has its own dangers if you don't anticipate what comes next.

Opioid overdose presents with the classic triad: miosis (pinpoint pupils), respiratory depression (rate below 12 breaths/min, shallow or absent respirations), and decreased level of consciousness. Cyanosis and hypotension follow as oxygen saturation plummets. The priority nursing intervention is maintaining the airway and administering naloxone (Narcan), an opioid antagonist. Naloxone works within 2–5 minutes IV but has a shorter half-life (30–90 minutes) than most opioids, meaning the patient can re-sedate and stop breathing again once naloxone wears off. Repeated doses or a continuous infusion may be needed, and the patient requires ongoing respiratory monitoring for at least 2 hours after the last dose. Titrate naloxone to restore adequate respirations — not full alertness — because abrupt full reversal precipitates acute withdrawal: agitation, vomiting, tachycardia, diaphoresis, and severe pain. For opioid use disorder management, medication-assisted treatment with methadone (full agonist, dispensed only through certified programs), buprenorphine (partial agonist, can be prescribed in outpatient settings), or naltrexone (antagonist, requires 7–10 days opioid-free before starting) reduces relapse and mortality.

Key Distinctions

Don't confuse opioid overdose (pinpoint pupils, bradypnea, sedation) with stimulant overdose (dilated pupils, tachycardia, agitation) — pupil size is your fastest differentiator. Students often think naloxone fully "fixes" the overdose, but its short half-life means re-sedation is the real danger. Methadone is a full agonist used for maintenance, while naltrexone is a pure antagonist that blocks opioid effects — giving naltrexone to someone still opioid-dependent triggers immediate withdrawal.

Clinical Pearl

Titrate naloxone to breathing, not waking. A fully alert post-overdose patient in acute withdrawal is vomiting, aspirating, and fighting — that's a new emergency.