When viewing this topic in a different language, you may notice some differences in the way the content is structured, but it still reflects the latest evidence-based guidance.

Acute asthma exacerbation in adults

Last reviewed: 6 Nov 2023
Last updated: 02 Nov 2023



History and exam

Key diagnostic factors

  • cough
  • wheezing
  • shortness of breath
  • chest tightness
  • sleep disturbance
  • accessory muscle use
  • tachypnea
  • tachycardia
  • wheezing, poor air movement, or diminished breath sounds
  • inability to speak
More key diagnostic factors

Other diagnostic factors

  • exercise limitation
  • stridor
  • cyanosis
Other diagnostic factors

Risk factors

  • viral infection
  • uncontrolled asthma symptoms
  • high use of short-acting beta-2 agonists
  • inconsistent use of inhaled corticosteroids
  • incorrect inhaler technique
  • low forced expiratory volume in 1 second (FEV₁)
  • high bronchodilator reversibility
  • current smoker (including e-cigarettes) or exposure to secondhand cigarette smoke
  • exposure to allergens (including history of seasonal allergic rhinitis)
  • air pollution
  • poor indoor air quality
  • obesity
  • chronic rhinosinusitis
  • gastroesophageal reflux disease
  • confirmed food allergy
  • history of asthma
  • history of hospitalization for asthma exacerbations
  • one or more severe exacerbations in the last 12 months
  • use of oral corticosteroids
  • poor adherence to asthma treatment
  • pregnancy
  • psychological or socioeconomic problems
  • elevated blood eosinophils
  • elevated fractional exhaled nitric oxide (FeNO)
  • respiratory bacterial infection
More risk factors

Diagnostic investigations

1st investigations to order

  • peak expiratory flow rate
  • oxygen saturation
More 1st investigations to order

Investigations to consider

  • ABG
  • chest x-ray
More investigations to consider

Treatment algorithm


life-threatening exacerbation or impending respiratory failure

severe exacerbation

mild to moderate exacerbation


symptomatic asthma



Sourav Majumdar, MD

Clinical Assistant Professor (Affiliated)

Division of Pulmonary, Allergy and Critical Care Medicine

Department of Medicine

Stanford University School of Medicine




SM declares that he has no competing interests.

Lauren Eggert, MD

Clinical Assistant Professor

Division of Pulmonary, Allergy and Critical Care Medicine

Department of Medicine

Stanford University School of Medicine




LE declares that she has participated on advisory boards for Regeneron and AstraZeneca.


Dr Sourav Majumdar and Dr Lauren Eggert would like to gratefully acknowledge Dr Ware Kuschner, Dr Michael Ezzie, and Dr Jonathan P. Parsons, the previous contributors to this topic.


WK and ME declare that they have no competing interests. JPP is a member of Speakers' Bureaus for GlaxoSmithKline, Schering-Plough, and AstraZeneca.

Peer reviewers

Anne Dixon, MD

Assistant Professor

Pulmonary and Critical Care Medicine

University of Vermont




AD declares that she has no competing interests.

Neil C. Thomson, MBChB, MD, FRCP

Professor of Respiratory Medicine

Institute of Infection, Immunity & Inflammation

University of Glasgow





NCT declares that he has no competing interests.

Graeme P. Currie, MBChB, MD, FRCP

Consultant Chest Physician

Chest Clinic C

Aberdeen Royal Infirmary





GPC declares that he has no competing interests.

  • Differentials

    • Acute bronchiolitis
    • Pneumonia
    • Foreign body/obstruction
    More Differentials
  • Guidelines

    • Global strategy for asthma management and prevention​
    • Focused updates to the asthma management guidelines: a report from the National Asthma Education and Prevention Program Coordinating Committee Expert Panel Working Group
    More Guidelines
  • Patient leaflets

    Asthma in adults

    More Patient leaflets
  • Videos

    Peak flow measurement: animated demonstration

    Expiratory wheeze

    More videos
  • padlock-lockedLog in or subscribe to access all of BMJ Best Practice

Use of this content is subject to our disclaimer