When is cough functional, and how should it be treated?

Abstract

Key points: Habit cough is most commonly characterised by a repetitive loud barking cough that persists for prolonged periods.The cough interferes with normal activity and substantially decreases the quality of life.The sine qua non is the total absence of this troublesome cough once asleep.The age distribution ranges from 4 years to late adolescence, with 85% of cases occurring from 8 to 14 years of age; similar cough in adults is much less common and poorly characterised.Pharmacological treatment is ineffective.A simple behavioural approach called suggestion therapy has been applied with success by many physicians.The natural history in the absence of treatment can result in persistence for months to years.

Educational aims: To increase awareness of functional cough as a non-organically caused symptom in children and adolescents.To provide the means of diagnosing a functional cough based on the distinguishing characteristics of this cause of chronic cough.To understand the principles of treating a functional cough with a simple behavioural technique called suggestion therapy.

Summary: Involuntary cough without an identified underlying organic reason has been given various names and recommended treatments. Current experience in children and adolescents suggests that "habit cough" best describes this entity, and suggestion therapy is a highly effective treatment that most physicians can learn.

Figure 1

Ages of 140 patients diagnosed with habit cough at the pediatric allergy–pulmonary clinic.

Figure 2

Duration of cough prior to diagnosis at the paediatric allergy–pulmonary clinic.