Advancing science is broadening our understanding of the potential mechanisms of chronic cough

View the animated diagram to learn about potential mechanisms of chronic cough

  • These potential mechanisms differ from the protective-cough reflex, which is important for clearing the airways of inhaled particles.1,5,7

Explore the common clinical characteristics of chronic cough8

Learn more about evolving scientific research on potential mechanisms of chronic cough2

The 2017 American College of Chest Physicians (Chest) Expert Panel Published Clinical Guidelines that Include Information for the Management of Chronic Cough9

The guidelines recommend following the steps summarized below:

Initial investigation

Conduct an initial investigation of
patients with chronic cough (>8 weeks) to assess patient history, which includes any red flags (shown below), occupational and environmental issues, travel exposures, physical exam, and chest radiograph. Always consider
smoking history, medications known to cause cough, and whether the cause of cough suggests a life-threatening condition.9

Underlying conditions

In patients whose initial assessment
does not reveal factors that may
contribute to cough, further
investigation into common underlying conditions (eg, asthma, GERD, UACS [postnasal drip], NAEB) is needed.9

Other investigations may be considered including swallow evaluations, sinus imaging, cardiac workup, and occupation assessments9

GERD, gastroesophageal reflux disease; UACS, upper airway cough syndrome; NAEB, nonasthmatic eosinophilic bronchitis
If cough persists

If cough persists despite appropriate investigation and treatment for underlying conditions, consider referral to a cough clinic for investigation of refractory chronic cough or unexplained chronic cough.9

What are potential red flags when assessing patients presenting with chronic cough?

Red flags include9:

  • Hemoptysis
  • Smoker >45 years with a new cough, change in cough, or coexisting voice disturbance
  • Aged 55-80 years: 30 pack-year smoking history, and current smoker or quit <15 years ago
  • Prominent dyspnea, especially at rest or at night
  • Hoarseness
  • Systemic symptoms, including fever, weight loss, and/or peripheral edema with weight gain
  • Trouble swallowing when eating or drinking
  • Vomiting
  • Recurrent pneumonia
  • Abnormal respiratory exam and/or abnormal chest radiograph coinciding with duration of cough

Important reminders9:

Check for red flags (shown above) and address them

  • Optimize therapy for each diagnosis
  • Check compliance during regularly scheduled and frequent follow-ups (assess for patient barriers to enactment or receipt of instructions)
  • Due to the possibility of multiple causes, maintain all partialIy effective treatment
  • Routinely assess for environmental and occupational factors
  • Routinely assess cough severity and HRQoL with validated tools
  • Routinely follow up with patient in 4-6 weeks
  • Consider a referral to a cough clinic for refractory cough

References: 1. Mazzone SB, Undem BJ. Physiol Rev. 2016;96:975-1024. 2. Mazzone SB et al. Lancet Respir Med. 2018;6:636-646. 3. Bonvini SJ, Belvisi MG. Pulm Pharmacol Ther. 2017;47:21-28. 4. West PW et al. Am J Respir Crit Care Med. 2015;192:30-39. 5. Smith JA, Badri H. J Allergy Clin Immunol Pract. 2019;7:1731-1738. 6. Canning BJ et al. Chest. 2014;146:1633-1648. 7. Canning BJ. Pulm Pharmacol Ther. 2011;24:295-299. 8. Morice AH et al. Eur Respir J. 2020;55:1901136. 9. Irwin RS et al. Chest. 2018;153:196-209.