EBM Consult

Morphine Use in Acute Coronary Syndrome (ACS, Acute Myocardial Infarction, NSTEMI, STEMI)



  • Due to a large observational study of 17,000 patients that found a higher risk of death for patients getting morphine, the ACC/AHA Guidelines for the management non-ST segment elevation myocardial infarction (NSTEMI) downgraded the recommendation for the use of morphine to a Class IIb recommendation.   The current 2014 ACC/AHA NSTEMI guidelines remain the same in this recommendation.
  • The 2010 ACLS guidelines also say it "may be considered" for pain relief.
  • Until further evaluation, the benefits of using morphine in the acute management of ACS should be done only after attempts to utilize other interventions that are known to be beneficial (such as aspirin, supplemental oxygen if hypoxic, nitrates, etc.)


  • Assuming no contraindications, the 2013 ACC/AHA guidelines for STEMI suggest that morphine is the drug of choice for pain relief. 
  • Dosing:  Initially morphine 4 - 8 mg IV (consider lower doses in elderly), then 2 - 8 mg IV every 5 to 15 min as needed.
  • Contraindications:  Known allergy, lethargy, hypotension, bradycardia.

Author:  Anthony J. Busti, MD, PharmD, FNLA, FAHA
Editors:  Dylan Kellogg, MD
Last Reviewed:  August 2015

Supporting Guidelines

  • 2014 AHA/ACC NSTEMI Guidelines: 
    "In the absence of contraindications, it may be reasonable to administer morphine sulfate intravenously to patients with NSTE-ACS if there is continued ischemic chest pain despite treatment with maximally tolerated anti-ischemic medications. (Class IIb, Level of Evidence: B)"

    • Reference: Amsterdam EA et al.  2014 AHA/ACC Guideline for the Management of Patients With Non-ST-Elevation Acute Coronary Syndromes: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.  Circulation 2014:[Epub ahead of print]. PubMed

    2013 AHA/ACC STEMI Guidelines: 
    "In the absence of a history of hypersensitivity, morphine sulfate is the drug of choice for pain relief in patients with STEMI, especially those whose course is complicated by acute pulmonary edema. It can alleviate the work of breathing, reduce anxiety, and favorably affect ventricular loading conditions. The dose of morphine sulfate needed to achieve adequate pain control will vary depending on patient age, body size, BP, and heart rate"

    • Reference: O'Gara PT et al.  2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines.  Circulation 2013;127(4):e362-425.  PubMed

    2010 AHA ACLS Guidelines: 
    "Morphine should be administered intravenously and titrated to pain relief in patients with STEMI. Morphine may be considered for pain relief in subjects with suspected NSTEMI." 

    • Reference: O'Connor RE et al. Part 9. Acute Coronary Syndromes: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations. Circulation 2010;122:S422-S465.  PubMed

Landmark or Original Studies

  • Meine TJ et al. Association of intravenous morphine use and outcomes in acute coronary syndromes: results from the CRUSADE Quality Improvement Initiative. Am Heart J 2005;149(6):1043-9. PubMed
  • Iakobishvili Z et al. Use of intravenous morphine for acute decompensated heart failure in patients with and without acute coronary syndromes. Acute Card Care 2011;13(2):76-80. PubMed

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MESH Terms or Keywords

  • Morphine NSTEMI, Mortality with Morphine ACS, Morphine STEMI, Morphine Heart Attack, Morphine MI