Last updated: September 6, 2022
Dyspnea, or shortness of breath, is a subjective feeling of breathing discomfort. It is a commonly reported symptom in acute care and outpatient settings. Causes of dyspnea include pulmonary (e.g., pneumonia, asthma exacerbation), cardiac (e.g., acute coronary syndrome, congestive heart failure), toxic-metabolic (e.g., metabolic acidosis, medication use), upper airway (e.g., epiglottitis, foreign body aspiration), psychological, and neuromuscular pathologies. On initial presentation, it is important to immediately evaluate the patient for any urgent or life-threatening causes of dyspnea using patient history, physical examination, and diagnostic testing. Once immediately life-threatening causes have been ruled out, a more detailed patient history should be obtained and further testing performed to narrow the differential diagnosis.
See also “Respiratory failure and arrest.”
Assume that all dyspnea is life-threatening until proven otherwise and perform the following steps concurrently, not sequentially.
Prioritize rapid identification and treatment of critical causes of dyspnea over advanced testing to obtain a definitive diagnosis. 
When evaluating a patient with dyspnea, always consider infection control and the need for PPE and patient isolation.
Red flags in dyspnea
The presence of any of these red flags suggests that dyspnea is the result of a serious pathologic process.
Anticipate rapid clinical deterioration in patients with red flag features.
Immediately life-threatening causes of dyspnea
See also “Rapidly reversible causes of respiratory failure.”
The severity of symptoms reported by the patient may not correlate with disease severity. Remain vigilant for life-threatening causes of dyspnea. 
Upper airway causes
Toxic-metabolic and other causes
Overview of causes of dyspnea by speed of onset
Cardiopulmonary disease may be mistaken for panic attacks, as symptoms and pathogenesis overlap. Consider organic causes before attributing dyspnea to anxiety. 
Mandell LA, Wunderink RG, Anzueto A, et al. Infectious Diseases Society of America/American Thoracic Society Consensus Guidelines on the Management of Community-Acquired Pneumonia in Adults. Clinical Infectious Diseases. 2007; 44
doi: 10.1086/511159 . | Open in Read by QxMD
Stoller JK. Acute Exacerbations of Chronic Obstructive Pulmonary Disease. N Engl J Med. 2002; 346
doi: 10.1056/nejmcp012477 . | Open in Read by QxMD
Global Initiative for Chronic Obstructive Lung Disease. Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease (2020 Report).
Accessed: June 27, 2019.
Guttikonda SNR, Vadapalli K. Approach to undifferentiated dyspnea in emergency department: aids in rapid clinical decision-making.. Int J Emergency Med. 2018; 11
doi: 10.1186/s12245-018-0181-z . | Open in Read by QxMD
Camargo CA, Rachelefsky G, Schatz M. Managing Asthma Exacerbations in the Emergency Department: Summary of the National Asthma Education and Prevention Program Expert Panel Report 3 Guidelines for the Management of Asthma Exacerbations. Proc Am Thorac Soc. 2009; 6
doi: 10.1513/pats.p09st2 . | Open in Read by QxMD
Vasileiadis I, Alevrakis E, Ampelioti S, Vagionas D, Rovina N, Koutsoukou A. Acid-Base Disturbances in Patients with Asthma: A Literature Review and Comments on Their Pathophysiology. J Clin Med. 2019; 8
doi: 10.3390/jcm8040563 . | Open in Read by QxMD
Leech C, Porter K, Steyn R, et al. The pre-hospital management of life-threatening chest injuries: A consensus statement from the Faculty of Pre-Hospital Care, Royal College of Surgeons of Edinburgh. Trauma. 2016; 19
doi: 10.1177/1460408616664553 . | Open in Read by QxMD
Leigh-Smith S, Harris T. Tension pneumothorax--time for a re-think?. Emergency Medicine Journal. 2004; 22
doi: 10.1136/emj.2003.010421 . | Open in Read by QxMD
Baumann MH, Strange C, Heffner JE, et al. Management of spontaneous pneumothorax: an American College of Chest Physicians Delphi consensus statement.. Chest. 2001; 119
doi: 10.1378/chest.119.2.590 . | Open in Read by QxMD
MacDuff A, Arnold A, Harvey J. Management of spontaneous pneumothorax: British Thoracic Society pleural disease guideline 2010. Thorax. 2010; 65
(Suppl 2): p.ii18-ii31.
doi: 10.1136/thx.2010.136986 . | Open in Read by QxMD
Kearon C, Akl EA, Ornelas J, et al. Antithrombotic Therapy for VTE Disease. Chest. 2016; 149
doi: 10.1016/j.chest.2015.11.026 . | Open in Read by QxMD
Kosova E, Bergmark B, Piazza G. Fat embolism syndrome. Circulation. 2015; 131
doi: 10.1161/CIRCULATIONAHA.114.010835 . | Open in Read by QxMD
Newbigin K, Souza CA, Armstrong M, et al. Fat embolism syndrome: Do the CT findings correlate with clinical course and severity of symptoms? A clinical-radiological study. Eur J Radiol. 2016; 85
doi: 10.1016/j.ejrad.2015.11.037 . | Open in Read by QxMD
Al-Salem A. The Acute Chest Syndrome in Sickle Cell Anemia.
Acute Chest Syndrome.
Updated: January 1, 2019.
Accessed: November 27, 2019.
ARDS Definition Task Force. Acute respiratory distress syndrome: the Berlin Definition. JAMA. 2012; 307
Gattinoni L, Marini JJ, Pesenti A, Quintel M, Mancebo J, Brochard L. The "Baby Lung" Became an Adult. Intensive Care Med. 2016; 42
doi: 10.1007/s00134-015-4200-8 . | Open in Read by QxMD
Amsterdam EA, Wenger NK, Brindis RG, et al.. 2014 AHA/ACC Guideline for the Management of Patients With Non–ST-Elevation Acute Coronary Syndromes. J Am Coll Cardiol. 2014
doi: 10.1016/j.jacc.2014.09.017 . | Open in Read by QxMD
O’Gara PT, Kushner FG, et al. 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction. Circulation. 2013; 127
doi: 10.1161/cir.0b013e3182742cf6 . | Open in Read by QxMD
Spodick DH. Acute Cardiac Tamponade. N Engl J Med. 2003; 349
doi: 10.1056/nejmra022643 . | Open in Read by QxMD
Long B, Koyfman A, Gottlieb M. Management of Heart Failure in the Emergency Department Setting: An Evidence-Based Review of the Literature. J Emerg Med. 2018; 55
doi: 10.1016/j.jemermed.2018.08.002 . | Open in Read by QxMD
Yancy CW, Jessup M, Bozkurt B, et al. 2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Failure Society of America. Circulation. 2017; 136
doi: 10.1161/cir.0000000000000509 . | Open in Read by QxMD
Yancy CW, Jessup M, Bozkurt B, et al. 2013 ACCF/AHA Guideline for the Management of Heart Failure: Executive Summary. J Am Coll Cardiol. 2013; 62
doi: 10.1016/j.jacc.2013.05.020 . | Open in Read by QxMD
Van Diepen S, Katz JN, Albert NM, et al. Contemporary Management of Cardiogenic Shock: A Scientific Statement From the American Heart Association. Circulation. 2017; 136
doi: 10.1161/cir.0000000000000525 . | Open in Read by QxMD
Gersh BJ, Maron BJ, Bonow RO, et al. 2011 ACCF/AHA Guideline for the Diagnosis and Treatment of Hypertrophic Cardiomyopathy: Executive Summary. J Am Coll Cardiol. 2011; 58
doi: 10.1016/j.jacc.2011.10.825 . | Open in Read by QxMD
Díez-López C, Salazar-Mendiguchía J. Clinical presentations of hypertrophic cardiomyopathy and implications for therapy. Global Cardiology Science and Practice. 2018; 2018
doi: 10.21542/gcsp.2018.19 . | Open in Read by QxMD
January CT, Wann LS, Alpert JS, et al. 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation. J Am Coll Cardiol. 2014; 64
doi: 10.1016/j.jacc.2014.03.022 . | Open in Read by QxMD
Gutierrez C, Blanchard DG. Diagnosis and Treatment of Atrial Fibrillation. Am Fam Physician. 2016
Karen K. Stout, Edward D. Verrier. Acute Valvular Regurgitation. Circulation. 2009; 119
doi: 10.1161/circulationaha.108.782292 . | Open in Read by QxMD
Loprinzi Brauer, et al.. Prospective Validation of the NIAID/FAAN Criteria for Emergency Department Diagnosis of Anaphylaxis. JACI: In Practice. 2016; 4
doi: 10.1016/j.jaip.2016.06.003 . | Open in Read by QxMD
Walls R, Hockberger R, Gausche-Hill M. Rosen's Emergency Medicine.
Elsevier Health Sciences
Campbell RL, Li JTC, Nicklas RA, Sadosty AT. Emergency department diagnosis and treatment of anaphylaxis: a practice parameter. Ann Allergy Asthma Immunol. 2014; 113
doi: 10.1016/j.anai.2014.10.007 . | Open in Read by QxMD
Long B, Koyfman A, Gottlieb M. Evaluation and Management of Angioedema in the Emergency Department. Western Journal of Emergency Medicine. 2019; 20
doi: 10.5811/westjem.2019.5.42650 . | Open in Read by QxMD
Moellman JJ, Bernstein JA, Lindsell C, et al. A Consensus Parameter for the Evaluation and Management of Angioedema in the Emergency Department. Academic Emergency Medicine. 2014; 21
doi: 10.1111/acem.12341 . | Open in Read by QxMD
Hewlett JC, Rickman OB et al.. Foreign body aspiration in adult airways: therapeutic approach. J Thorac Dis. 2017; 9
doi: 10.21037/jtd.2017.06.137 . | Open in Read by QxMD
Alcaide ML, Bisno AL. Pharyngitis and Epiglottitis. Infect Dis Clin North Am. 2007; 21
doi: 10.1016/j.idc.2007.03.001 . | Open in Read by QxMD
Lindquist B et al.. Adult Epiglottitis: A Case Series. The Permanente Journal. 2016
doi: 10.7812/tpp/16-089 . | Open in Read by QxMD
Maroldi R, Farina D, Ravanelli M, Lombardi D, Nicolai P. Emergency Imaging Assessment of Deep Neck Space Infections. Seminars in Ultrasound, CT and MRI. 2012; 33
doi: 10.1053/j.sult.2012.06.008 . | Open in Read by QxMD
Dargan PI. An evidence based flowchart to guide the management of acute salicylate (aspirin) overdose. Emergency Medicine Journal. 2002; 19
doi: 10.1136/emj.19.3.206 . | Open in Read by QxMD
American College of Medical Toxicology. Guidance Document: Management Priorities in Salicylate Toxicity. J Med Toxicol. 2015; 11
doi: 10.1007/s13181-013-0362-3 . | Open in Read by QxMD
Hulse EJ, Davies JOJ, Simpson AJ, Sciuto AM, Eddleston M. Respiratory Complications of Organophosphorus Nerve Agent and Insecticide Poisoning. Implications for Respiratory and Critical Care. Am J Respir Crit Care Med. 2014; 190
doi: 10.1164/rccm.201406-1150ci . | Open in Read by QxMD
Kitabchi AE, Umpierrez GE, Miles JM, Fisher JN. Hyperglycemic Crises in Adult Patients With Diabetes. Diabetes Care. 2009; 32
doi: 10.2337/dc09-9032 . | Open in Read by QxMD
Westerberg D. Diabetic Ketoacidosis: Evaluation and Treatment. Am Fam Physician. 2013
Hampson NB, Piantadosi CA, Thom SR, Weaver LK. Practice Recommendations in the Diagnosis, Management, and Prevention of Carbon Monoxide Poisoning. Am J Respir Crit Care Med. 2012; 186
doi: 10.1164/rccm.201207-1284ci . | Open in Read by QxMD
Hampson NB. Myth busting in carbon monoxide poisoning. Am J Emerg Med. 2016; 34
doi: 10.1016/j.ajem.2015.10.051 . | Open in Read by QxMD
Updated: April 24, 2019.
Accessed: November 6, 2019.
Carson JL, Guyatt G, Heddle NM, et al. Clinical Practice Guidelines From the AABB: Red Blood Cell Transfusion Thresholds and Storage. JAMA. 2016; 316
doi: 10.1001/jama.2016.9185 . | Open in Read by QxMD
Berliner D, Schneider N, Welte T, Bauersachs J. The differential diagnosis of dyspnea. Dtsch Arztebl Int. 2016; 113
doi: 10.3238/arztebl.2016.0834 . | Open in Read by QxMD
Qaseem A, Etxeandia-Ikobaltzeta I, Mustafa RA, et al. Appropriate Use of Point-of-Care Ultrasonography in Patients With Acute Dyspnea in Emergency Department or Inpatient Settings: A Clinical Guideline From the American College of Physicians. Ann Intern Med. 2021; 174
doi: 10.7326/m20-7844 . | Open in Read by QxMD
Parshall MB, Schwartzstein RM, Adams L, et al. An Official American Thoracic Society Statement: Update on the Mechanisms, Assessment, and Management of Dyspnea. Am J Respir Crit Care Med. 2012; 185
doi: 10.1164/rccm.201111-2042st . | Open in Read by QxMD
DeVos E, Jacobson L. Approach to Adult Patients with Acute Dyspnea. Emerg Med Clin North Am. 2016; 34
doi: 10.1016/j.emc.2015.08.008 . | Open in Read by QxMD
Kapos I, Tanner F. Value of echocardiography in differentiation of acute dyspnoea. Cardiovascular Medicine. 2017; 20
doi: 10.4414/cvm.2017.00489 . | Open in Read by QxMD
Raja AS, Greenberg JO, Qaseem A, et al. Evaluation of Patients With Suspected Acute Pulmonary Embolism: Best Practice Advice From the Clinical Guidelines Committee of the American College of Physicians. Ann Intern Med. 2015; 163
doi: 10.7326/m14-1772 . | Open in Read by QxMD
Kline JA, Garrett JS, Sarmiento EJ, Strachan CC, Courtney DM. Over-Testing for Suspected Pulmonary Embolism in American Emergency Departments. Circ Cardiovasc Qual Outcomes. 2020; 13
doi: 10.1161/circoutcomes.119.005753 . | Open in Read by QxMD
Zoorob RJ, Campbell JS. Acute dyspnea in the office.. Am Fam Physician. 2003; 68
Morgan WC, Hodge HL. Diagnostic evaluation of dyspnea.. Am Fam Physician. 1998; 57
Jameson JL, Fauci AS, Kasper DL, Hauser SL, Longo DL, Loscalzo J. Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2).
McGraw-Hill Education / Medical
Clark N, Fan VS, Slatore CG, et al. Dyspnea and Pain Frequently Co-occur among Medicare Managed Care Recipients. Ann Am Thorac Soc. 2014; 11
doi: 10.1513/annalsats.201310-369oc . | Open in Read by QxMD
Cader RA, Thoriappa K, Mohd R, Kong WY, Mustafar R, Kamaruzaman L. Breathlessness worsened by haemodialysis. Respir Med Case Rep. 2019; 26
doi: 10.1016/j.rmcr.2018.10.022 . | Open in Read by QxMD
Smoller JW, Pollack MH, Otto MW, Rosenbaum JF, Kradin RL. Panic anxiety, dyspnea, and respiratory disease. Theoretical and clinical considerations.. Am J Respir Crit Care Med. 1996; 154
doi: 10.1164/ajrccm.154.1.8680700 . | Open in Read by QxMD
Hampson NB, Courtney TG, Holm JR. Diffusion of Carbon Monoxide Through Gypsum Wallboard. JAMA. 2013; 310
doi: 10.1001/jama.2013.43127 . | Open in Read by QxMD
Frossard JL, Spahr L, Queneau PE, et al. Erythromycin intravenous bolus infusion in acute upper gastrointestinal bleeding: A randomized, controlled, double-blind trial. Gastroenterology. 2002; 123
doi: 10.1053/gast.2002.34230 . | Open in Read by QxMD
Caro DA. Basic Airway Management.
: p. 1-7
American Thoracic Society. International Consensus Conferences in Intensive Care Medicine: Noninvasive Positive Pressure Ventilation in Acute Respiratory Failure. Am J Respir Crit Care Med. 2001; 163
doi: 10.1164/ajrccm.163.1.ats1000 . | Open in Read by QxMD
Thim T, Krarup NHV, Grove EL, Rohde CV, Lofgren B. Initial assessment and treatment with the Airway, Breathing, Circulation, Disability, Exposure (ABCDE) approach. Int J Gen Med. 2012; 5
doi: 10.2147/ijgm.s28478 . | Open in Read by QxMD
Rochwerg B, Brochard L, Elliott MW, et al. Official ERS/ATS clinical practice guidelines: noninvasive ventilation for acute respiratory failure. Eur Respir J.. 2017; 50
doi: 10.1183/13993003.02426-2016 . | Open in Read by QxMD
Juurlink DN, Gosselin S, Kielstein JT, et al. Extracorporeal Treatment for Salicylate Poisoning: Systematic Review and Recommendations From the EXTRIP Workgroup. Ann Emerg Med. 2015; 66
doi: 10.1016/j.annemergmed.2015.03.031 . | Open in Read by QxMD
Stolbach AI, Hoffman RS, Nelson LS. Mechanical Ventilation Was Associated with Acidemia in a Case Series of Salicylate-poisoned Patients. Academic Emergency Medicine. 2008; 15
doi: 10.1111/j.1553-2712.2008.00205.x . | Open in Read by QxMD
Lawson-Smith P, Jansen EC, Hyldegaard O. Cyanide intoxication as part of smoke inhalation - a review on diagnosis and treatment from the emergency perspective. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 2011; 19
doi: 10.1186/1757-7241-19-14 . | Open in Read by QxMD
Updated: January 1, 2019.
Accessed: November 15, 2019.
Endotracheal Intubation by Direct Laryngoscopy.
Updated: May 1, 2004.
Accessed: November 15, 2019.
Lieberman P, Nicklas RA, Randolph C, et al. Anaphylaxis—a practice parameter update 2015. Annals of Allergy, Asthma & Immunology. 2015; 115
doi: 10.1016/j.anai.2015.07.019 . | Open in Read by QxMD
January CT, Wann LS, Calkins H, et al. 2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation. J Am Coll Cardiol. 2019; 74
doi: 10.1016/j.jacc.2019.01.011 . | Open in Read by QxMD
Lewis SR, Butler AR, Parker J, Cook TM, Schofield-Robinson OJ, Smith AF. Videolaryngoscopy versus direct laryngoscopy for adult patients requiring tracheal intubation: a Cochrane Systematic Review. Br J Anaesth. 2017; 119
doi: 10.1093/bja/aex228 . | Open in Read by QxMD
Apfelbaum JL, Hagberg CA, Caplan RA, et al. Practice Guidelines for Management of the Difficult Airway. Anesthesiology. 2013; 118
doi: 10.1097/aln.0b013e31827773b2 . | Open in Read by QxMD
Gregor P, Čurila K. Medical treatment of hypertrophic cardiomyopathy - What do we know about it today?. Cor Vasa. 2015; 57
doi: 10.1016/j.crvasa.2015.02.003 . | Open in Read by QxMD
Casu G, Merella P. Diuretic Therapy in Heart Failure – Current Approaches. European Cardiology Review. 2015; 10
doi: 10.15420/ecr.2015.10.01.42 . | Open in Read by QxMD
V. Sherrid M. Drug Therapy for Hypertrophic Cardiomypathy: Physiology and Practice. Current Cardiology Reviews. 2016; 12
doi: 10.2174/1573403x1201160126125403 . | Open in Read by QxMD