The Analgesic Efficacy and Safety of Intramuscular Hydromorphone Versus Butorphanol for Acute Pain in the Emergency Department: A Randomized Trial

BACKGROUND: Acute pain represents a distressing encounter for most patients in the emergency department (ED), profoundly impacting their quality of life. Nonsteroidal anti-inflammatory drugs (NSAIDs) and morphine represent the most widely utilized analgesics; however, their clinical application in acute pain management is limited by their delayed onset of pharmacological action or significant risk of addiction. This study aimed to evaluate and compare the analgesic efficacy and safety of intramuscular hydromorphone and butorphanol in patients with acute pain in the ED. METHODS: This randomized controlled clinical trial randomly divided 199 patients with moderate to severe acute pain into two groups in a 1:1 ratio, receiving intramuscular injections of 1 mg of hydromorphone or butorphanol, respectively. Primary outcomes included pain intensity changes measured by the numerical rating scale (NRS), while secondary outcomes encompassed supplemental analgesic requirements, vital sign alterations, adverse event incidence, and patients' destination. RESULTS: Comparative analysis revealed that hydromorphone administration resulted in significantly greater NRS score reductions compared to butorphanol, with superior pain relief rates observed at both 1 (56% vs. 44%, p = 0.013) and 2 h (69% vs. 60%, p = 0.002) intervals, and a greater proportion of apparent relief at 2 h (88% vs. 69%, p = 0.002), particularly in cases of severe pain (78% vs. 56%, p = 0.001). The hydromorphone group demonstrated significantly lower supplemental analgesic requirements at 2 h postadministration (0.0% vs. 6.1%, p = 0.031). There was no significant difference in the incidence of adverse reactions, the final destination, and the effects on heart rate, respiration, and oxygen saturation between the two groups. Common adverse reactions included dizziness or headache, nausea or vomiting, and injection pain. CONCLUSION: Both hydromorphone and butorphanol were effective and safe in alleviating moderate to severe acute pain in the ED. However, hydromorphone exhibited superior analgesic effectiveness and a more rapid onset of action compared to butorphanol, particularly in cases of severe pain. TRIAL REGISTRATION: Chinese Registry of Clinical Trial: ChiCTR2400088376.