A persistent cough, also known as nagging cough, is described a cough that persists for a period of 8 weeks or longer among adults or 4 weeks or longer in children. The cough may manifest in two different ways; it may be dry or productive. By being productive, this means that an individual may or may not cough up mucus. In addition to it being known as a nagging cough, a persistent cough also has other terminologies including lingering or chronic cough.

Symptoms of Persistent Cough

Some of the common symptoms that may occur alongside a persistent cough include:

• Sore through
• Postnasal drip – sensation that a substance is dripping down at the back of the throat
• Hoarseness
• Sour taste in the mouth
• Running nose
• Frequent clearing of the throat
• Stuffy nose
• Heartburn

Possible Causes of Persistent Cough

Although it can be challenging to specifically know what the cause of a persistent cough is, there are quite a number of possible causes and they are normally classified into two categories. Common and relatively rare causes. Some of these are likely to affect children more than adults and the other way around.

Common Causes of a Persistent Cough in Adults

Some of the common causes of a persistent cough in adults include:

Asthma: Wheezing and shortness of breath are the most common symptoms of asthma. In some individuals with asthma, a cough may be the only symptom.

Post-nasal drip: These are secretions from the nose that drain down into throat. They can lead to congestion and coughing. Post-nasal drip is usually caused by allergies or the common cold. The condition makes an individual to constantly want to clear the throat.

Acid Reflux: This is a condition whereby contents from an individual’s stomach move up back into the esophagus. It is also known as gastroesophageal reflux. Gastroesophageal is one of the most common causes a of chronic cough and a cough due GERD in most cases worsens at night when an individual lies down in bed.

Eosinophilic Bronchitis: This is a type of airway inflammation due to excessive mast cell recruitment and activation in the superficial airways as opposed to the smooth muscles of the airways.

Infections: Although an individual may have a persistent cough when they have a cold, flu or pneumonia, after these conditions heal, the cough may still remain for a period of time.

Whooping cough: This is a condition that occurs as a result of infection of the respiratory tract.

Blood pressure medication: These may lead to a chronic dry cough.

Common Causes of Persistent Cough in Children

• Asthma
• Upper airway cough syndrome
• Protracted bacterial bronchitis
• Whooping cough

Other Common Causes of Persistent Cough

• Medications, especially for conditions treated with ACE inhibitors can lead to a chronic cough
• Upper airway cough syndrome
• Chronic bronchitis
• Infection
• Smoking
• Tumor

Diagnosis of Chronic Cough

During the diagnosis of a persistent cough, the first thing a specialist will do depending on the severity of the cough is controlling the patient’s symptoms so as to make them comfortable. Afterwards, tests will be commended to determine the cause of the cough.

A medical history of the patient is checked, and the patient is also asked questions about the risk factors for certain conditions which may cause the cough. Chest X-rays are usually conducted first. However, the said chest X-rays can sometimes miss the causes of a chronic cough. CT-scans can also be performed to confirm if there is any evidence of a tumor or infection.

Other tests that can be recommended include:

• Pulmonary function test which can be used to screen conditions like asthma and empyema.
• Esophageal pH testing – this checks the presence of acid reflux
• Allergy tests
• Laryngoscopy – this is used to examine the patient’s throat and voice box
• Bronchoscopy – used to check for foreign bodies or to evaluate the patient’s airways for a tumor.

Treatment of Persistent Cough

After a definitive diagnosis, the treatment of persistent cough is immediately started. The treatment modality is dependent on the underlying cause and the degree to which the patient’s cough is interfering with his/her day-to-day activities.