How is chronic cough diagnosed and treated?

A very detailed medical history and physical examination will frequently suffice to determine the major factors that contribute to a chronic cough.

The main purpose of this activity is to determine the trigger mechanisms. Unless these are eradicated, the treatment of the chronic cough will be unsuccessful. Frequently, the associated symptoms and physical findings provide an answer as to the cause. In specific situations such as suspected asthma, cancer or acid reflux, further specialised tests may be needed.

Examples include:

• Lung-function testing
• Chest XR with or without a CT scan
• Gastroscopy or Barium swallow

The success of treating patients with a chronic cough lies in the ability of the doctor to evaluate and eliminate the causative factors and doesn't rely on symptomatic relief measures such as cough suppressants. Most cough mixtures are ineffective in these situations.

Specific treatment of the underlying causes is indicated if any specific cause is identified. In situations where the possibility of post-nasal drip exists, but no clear signs are present, a trial of therapy is entirely appropriate. Sometimes two conditions may co-exist (asthma and post-nasal drip), leading to the cough. Treatment of both conditions is thus indicated.

The process of investigation and treatment is often slow and frustrating for both the patient and the doctor. In addition to a lot of patience from both parties, a thorough and systematic approach is required to get to the bottom of a chronic cough where the simple treatments have had no effect.