Reversal of Opioid-Induced Ventilatory Depression Using Low-Dose Naloxone (0.04 mg): a Case Series

Introduction Naloxone is commonly administered in emergency department (ED) to reverse opioid intoxication. Several naloxone dose recommendations exist for acute management of opioid intoxication based on limited published clinical data. A case series of ED patients with opioid-induced ventilatory depression that was reversed using a low-dose naloxone (0.04 mg with titration) is presented. Methods ED patients with opioid-induced ventilatory depression requiring naloxone administration were identified through medical toxicology consultation. Retrospective review of medical records was performed. Collected data included history, and pre- and post-naloxone data, including respiratory rate (RR), pulse oximetry (pulse ox), end-tidal CO 2 level (ET-CO 2 ), and Richmond Agitation Sedation Scale (RASS). Results Fifteen ED patients with moderate to severe opioid-induced ventilatory depression (median RR, 6 breaths/min) who were managed using low-dose naloxone strategy were identified. Twelve of 15 patients reported ingestion of methadone (range, 30 to 180 mg). The median naloxone dose of 0.08 mg (range, 0.04 to 0.12 mg) reversed opioid-induced ventilatory and CNS depression. Two patients experienced acute opioid withdrawal after receiving 0.08 mg. Conclusion ED patients with moderate to severe opioid-induced ventilatory depression can be reversed using 0.04 mg IV naloxone with appropriate dose titration.