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Asthma in adults

Last reviewed: 28 Oct 2023
Last updated: 31 Oct 2023



History and exam

Key diagnostic factors

  • recent upper respiratory tract infection
  • dyspnea
  • cough
  • expiratory wheezes
  • nasal polyposis
More key diagnostic factors

Risk factors

  • family history
  • allergens
  • atopic history
  • cigarette smoking or vaping
  • respiratory viral infection early in life
  • low socioeconomic status
  • nasal polyposis
  • obesity
  • gastroesophageal reflux disease (GERD)
  • obstructive sleep apnea
More risk factors

Diagnostic investigations

1st investigations to order

  • FEV₁/FVC ratio
  • peak expiratory flow rate (PEFR)
  • CXR
  • CBC
  • fractional exhaled nitric oxide (FeNO)
More 1st investigations to order

Investigations to consider

  • bronchial challenge test
  • immunoassay for allergen-specific IgE
  • skin prick allergy testing
More investigations to consider

Emerging tests

  • sputum eosinophil count

Treatment algorithm


initial treatment: infrequent asthma symptoms (e.g., less than twice a month) and no risk factors for exacerbations

initial treatment: asthma symptoms or need for a reliever twice a month or more (but less than 4-5 days per week)

initial treatment: troublesome asthma symptoms most days, or waking due to asthma once a week or more, especially if any risk factors exist

initial treatment: severely uncontrolled asthma or acute exacerbation


ongoing treatment: step 1 (symptoms less than twice a month and no exacerbation risk factors)

ongoing treatment: step 2 (asthma not controlled on step 1 treatment)

ongoing treatment: step 3 (asthma not controlled on step 2 treatment)

ongoing treatment: step 4 (asthma not controlled on step 3 treatment)

ongoing treatment: step 5 (asthma not controlled on step 4 treatment and patient reviewed by specialist)



Lauren E. Eggert, MD

Clinical Assistant Professor

Division of Pulmonary, Allergy, and Critical Care Medicine

Department of Medicine

Stanford University School of Medicine




LEE has participated on advisory boards for Regeneron and AstraZeneca.

Sourav Majumdar, MD

Clinical Assistant Professor (Affiliated)

Division of Pulmonary and Critical Care Medicine

Department of Medicine

Stanford University School of Medicine




SM declares that he has no competing interests.


Dr Lauren E. Eggert and Dr Sourav Majumdar would like to gratefully acknowledge Dr Irwani Ibrahim, Dr Kay Choong See, Dr Francis Thien, and Dr Catherine Weiler, previous contributors to this topic.


II, KCS, FT, and CW declare that they have no competing interests.

Peer reviewers

Javed Sheikh, MD

Clinical Director

Division of Allergy and Inflammation

Beth Israel Deaconess Medical Center/Harvard Medical School




JS is a consultant for Aventis, GSK, and Novartis/Genentech; is on the Speakers Bureau for Merck, Aventis, GSK, AstraZeneca, Pfizer, Novartis/Genentech, Inspire, and UCB; has had research sponsored by GSK; is an expert witness at Haemonetics; and has received publication honorarium at Emedicine.

Sheree M.S. Smith, PhD

Research Manager

Imperial College Healthcare Trust

NHLI Airways Division

Imperial College London (Honorary) Respiratory Research

Chest & Allergy

St Mary's Hospital




SMSS declares that she has no competing interests.

Neil Thomson, MBChB, MD, FRCP

Professor of Respiratory Medicine

Respiratory Medicine Section

Division of Immunology, Infection & Inflammation

University of Glasgow




NT declares that he has no competing interests.

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