Dry Cough
Coughing occurs naturally when the body wants to clear the upper airways. When it is dry, no mucus is produced or expelled.
Symptoms and Causes
Dry cough is a reflex action that occurs to clear the throat and airways of irritants without producing or expelling mucus. Also known as a non-productive cough, it is a sign of proper immune system function, as it protects the body by expelling harmful substances from the respiratory tract.
The prognosis of dry cough is good in most cases, as it is usually harmless and not indicative of a serious condition. Even so, when it is persistent, it negatively affects patients' quality of life.
Symptoms
Dry cough is one of the most common symptoms in clinical practice. Its main characteristics are:
- A tickling, itching, or throat-clearing sensation in the throat, which is why it is also known as an irritative cough.
- No phlegm or mucus is expelled.
- It is usually persistent and presents as coughing fits that are especially intense at night, thereby disrupting sleep.
Dry cough is frequently accompanied by other symptoms, such as:
- Throat irritation causing a tickling sensation.
- Sore throat.
- Hoarseness.
- Aphonia: total or partial loss of voice.
- Nasal congestion.
Causes
Conditions that commonly cause dry cough include:
- Viral infections: it is usually associated with the common cold, influenza, laryngitis, or COVID-19.
- Pharyngitis: inflammation and irritation of the mucosa lining the inside of the pharynx as a result of a bacterial or viral infection.
- Allergies: exposure to allergens such as pollen, dust, or animal dander may trigger an abnormal immune system reaction.
- Environmental irritants, such as tobacco smoke, pollution, chemicals, or very dry air.
- Asthma: chronic inflammation of the bronchi that causes breathing difficulties, wheezing, and coughing, especially after exercise and at night.
- Gastroesophageal reflux disease (GERD): stomach acid rises through the oesophagus and may reach and irritate the throat. In these cases, chronic cough often develops.
- Side effects of certain medications.
Dry cough is very common in children following influenza or a common cold and persists until residual mucus has completely cleared. When it occurs mainly at night or after exercise, it is often a symptom of asthma.
Risk Factors
The risk of dry cough increases in the following situations:
- Smoking.
- Exposure to irritants, pollution, or dry environments (heating systems or air conditioning).
- Weakened immune system.
Complications
When dry cough is severe or prolonged, it may lead to the following complications:
- Sleep disturbance and daytime fatigue.
- Insomnia.
- Headaches.
- Dizziness.
- Cough syncope: fainting triggered by coughing.
- Chest or abdominal muscle pain due to the effort involved in coughing.
- Persistent aphonia or hoarseness.
- Stress urinary incontinence.
Which doctor treats dry cough?
Dry cough is most commonly managed in the specialties of Pediatrics or Family and community medicine. When the cough is persistent, becomes chronic, or is accompanied by other symptoms, specialists in Pulmonology, Otorhinolaryngology, or Allergology may also be involved.
Diagnosis
The procedure used to diagnose the underlying condition responsible for dry cough is generally as follows:
- Medical history: information is gathered regarding the patient's medical history and the characteristics of the cough (duration, time of onset). Possible triggers and associated symptoms are also assessed.
- Physical examination:
- Visual examination of the throat and airways to identify inflammation, signs of infection, or the presence of phlegm and mucus.
- Observation of the chest to assess respiratory movements.
- Auscultation: the chest is listened to in order to detect wheezing (whistling sounds during breathing caused by airflow through narrowed airways) or crackles (crackling or bubbling sounds in the lungs during breathing).
- Complementary tests: if the cough persists or warning signs are present (shortness of breath, severe chest pain on breathing, fever, coughing up blood, weight loss, or symptoms lasting more than four weeks):
- Chest X-ray: X-rays are used to obtain images of the lungs, airways, heart, chest bones, and blood vessels.
- Spirometry: measures the amount of air the lungs can hold and the time required to expel it. To perform the test, the patient inhales as much air as possible and then exhales forcefully and as quickly as possible into a tube connected to a device that records the volume and speed of expelled air (spirometer).
- Allergy testing: detects abnormal reactions to specific allergens through controlled exposure.
Treatment
Dry cough can be relieved in the following ways to improve the patient's quality of life:
- Home remedies: drinking plenty of fluids, using a humidifier, or soothing throat irritation with honey or sugar-free lozenges.
- Medications: if the cough persists or interferes with sleep, the specialist may prescribe an antitussive cough syrup.
To completely relieve symptoms, it is necessary to apply specific treatment for the underlying condition:
- Viral infections: these resolve spontaneously after several days. Anti-inflammatory drugs, antipyretics, and analgesics help relieve associated symptoms.
- Pharyngitis: when bacterial in origin, antibiotics are required to treat the infection.
- Allergies: avoiding exposure to the allergen is essential. When this is not possible, the specialist prescribes antihistamines or corticosteroids. Allergy immunotherapy can provide long-term immunity enhancement, lasting up to five years.
- Asthma: inhaled corticosteroids and bronchodilators are highly effective in reducing inflammation and improving breathing.
- Gastroesophageal reflux disease (GERD): following a balanced diet and adopting healthy lifestyle habits are essential, including maintaining an ideal weight, quitting smoking, and avoiding alcohol consumption. In some cases, antacids or medications that reduce gastric acid production are required. More severe cases may require fundoplication, a surgical procedure that restores the function of the lower oesophageal sphincter.
