Several causes and treatment options for coughing.😷😷😷

Cough is a very common symptom. Although coughing is generally not very harmful, chronic coughing can be very annoying and damage the respiratory tract. Many different diseases can cause cough symptoms. This article will introduce the diagnosis, pathogenesis of coughs, and guidelines for their treatment.

1. Cough caused by the common cold.

The most common cause of colds is a viral infection. In addition to coughing, its clinical manifestations are also accompanied by upper respiratory tract-related symptoms such as throat irritation or discomfort, runny nose, nasal congestion, sneezing, postnasal drip, and fever. There are usually few systemic symptoms. Postnasal drip is often associated with coughing of the common cold.

Treatment method: 

• Central antitussive drugs such as codeine are generally not recommended for routine use alone in coughs of the common cold. 
• Antitussives in combination with decongestants and first-generation antihistamines are recommended for adults with the common cold with cough.
• For the common cold with cough, first-generation antihistamines alone have no obvious therapeutic benefit. Combining first-generation antihistamines and decongestants can effectively improve symptoms such as sneezing, nasal congestion, and relieve cough.
• It is not recommended to use NSAIDs if a patient with the common cold has no symptoms of headache, muscle pain, and fever.

2. Cough caused by acute tracheitis and bronchitis.

Most of acute tracheitis and bronchitis are caused by viruses and a few are caused by bacteria. Its initial clinical manifestations are symptoms of upper respiratory tract infection. The cough then gradually intensifies and with or without expectoration. The expectoration caused by bacterial infection is yellow and purulent sputum. 

Treatment method: 

• Antitussives should be used in patients with severe cough without sputum. Mucolytic or expectorant is recommended for patients who have sputum but cannot expectorate it. 
• Symptoms of acute respiratory infection can be relieved with extended-release guaifenesin. It can irritate the gastric mucosa and reflexively cause an increase in airway secretions. Increased secretions reduce the viscosity of phlegm. It also has a bronchodilator effect, which can enhance the effect of expectoration.
• Routine antimicrobial therapy is generally not recommended unless the patient has yellow and purulent sputum. Antibiotics may also be considered in patients with elevated peripheral white blood cell counts.

3. Cough after a cold.

The cough persist for 3 to 8 weeks after the acute respiratory symptoms of the cold disappeared, and the chest X-ray examination was no significant abnormal. 

Treatment method: 

• In the short term, decongestants, antihistamines, and antitussives can be recommended to treat some patients with obvious cough symptoms.
• Inhaled montelukast and corticosteroids are not recommended.

4. Cough caused by postnasal drip syndrome.

The nose produces secretions due to disease and the secretions flow back to the back of the nose and throat. It stimulates the cough receptors and causes coughing. The main clinical manifestation of postnasal drip syndrome is chronic cough. Coughing more during the day or during postural changes and less after falling asleep.

Treatment method: 

• Oral first-generation antihistamines and decongestants are the first recommended treatment for postnasal drip syndrome caused by the common cold and nonallergic rhinitis.
• Oral second-generation antihistamines and nasal inhaled corticosteroids are recommended first for the treatment of postnasal drip syndrome caused by the common cold and allergic rhinitis. For allergic rhinitis, leukotriene receptor antagonist therapy is also effective.
• To avoid unnecessary surgery, nasal inhaled corticosteroids are recommended for the treatment of chronic sinusitis with nasal polyps.
• Sequential treatment of oral corticosteroids and topical nasal inhaled corticosteroids is more effective than nasal inhaled corticosteroids alone in patients with chronic rhinosinusitis with nasal polyps.
• Nasal decongestants can relieve nasal congestion. It will reduce the congestion and edema of the nasal mucosa, thereby facilitating the drainage of secretions. However, patients should be alert to its adverse reactions when using it. It can cause drug-induced rhinitis and should not be used for a long time. Its course of treatment is generally less than 1 week. It recommends a combination of nasal decongestants and first-generation oral antihistamines. Their course of treatment is 2 to 3 weeks.
• For the treatment of patients with chronic sinusitis, mucolytics (such as carbocisteine, erdosteine) may be beneficial. It can also be used to flush the nasal cavity with saline.

5. Gastroesophageal reflux cough.

One of the common causes of chronic cough is the reflux of stomach acid and other stomach contents into the esophagus, which causes a cough. This cough occurs mostly during the day, with upright and postural changes. It generally has no phlegm or a small amount of white sticky phlegm. Greasy and acidic foods can trigger or aggravate a cough. 40 to 68% of patients also experience typical acid reflux symptoms such as acid reflux, belching and retrosternal burning.

Treatment method: 

• Acid-suppressing drugs, including potassium-competitive acid blockers (such as vonoprazan) and proton pump inhibitors (such as omeprazole), are the first choice of treatment.
• Gastroprokinetic agents (such as mosapride) can relieve symptoms associated with acid reflux. It can be used in combination with acid-suppressing drugs. The anti-reflux course of treatment is at least 8 weeks, and then the dose is gradually reduced.

6. Cough variant asthma.

It is a specific type of asthma. It is also one of the most common causes of chronic cough. Its main clinical manifestation is irritating dry cough. The cough is generally severe and occurs at night and in the early morning. It generally has no obvious symptoms such as shortness of breath or gasp for breath, but there will be airway hyperresponsiveness. 

Treatment method: 

• Treatment with inhaled corticosteroids alone or in combination with bronchodilators (such as long acting β2-agonist) is recommended.
• Classic asthma may be prevented with long-term use of inhaled corticosteroids.
• Leukotriene receptor antagonists, such as montelukast, reduce symptoms of airway inflammation and cough. It improves quality of life and is effective in treating cough variant asthma.

7. Eosinophilic bronchitis.

About 13 to 22% of chronic coughs are caused by eosinophilic bronchitis. The necessary basis for diagnosis is elevated sputum eosinophils. Chronic irritating cough is usually the only clinical symptom. It is usually a dry cough or with a little white mucus sputum. Cough is more common during the day, and occasionally at night. Cough triggers are mostly cold air, dust, odors or smoke. The patient had no associated symptoms of airway restriction such as dyspnea and gasp for breath.

Treatment method: 

• Cough was significantly relieved or disappeared soon after glucocorticoid treatment. Inhaled corticosteroids such as fluticasone propionate aerosol are the recommended first-line therapy. It should be used continuously for more than 8 weeks.
• Oral prednisone (10 to 20 mg daily for 3 to 5 days) can be combined for initial treatment.
• More than half of patients still relapse after treatment. Patients with persistent eosinophilic inflammation and rhinitis are risk factors for recurrence.

8. Allergic cough.

Some patients with chronic cough have normal sputum eosinophils and no hyperresponsive airways, but the patients are atopic. Effective with antihistamines and glucocorticoid therapy. This type of cough is called allergic cough. Cough occurs during the day or night, mostly paroxysmal and irritating dry cough. Cold air, dust, smoke, and talking can all induce coughing and often an itchy throat. 

Patients with allergic cough have one of the following indications:

1. Antihistamines or glucocorticoids are effective.
2. Positive skin test for allergens.
3. Increased serum total IgE or specific IgE.
4. History of allergic disease or exposure to allergens.

Treatment method: 

• Initial treatment can be short-term low-dose oral glucocorticoids for 3 to 5 days. Oral antihistamines and/or inhaled corticosteroids for more than 4 weeks.

9. Refractory chronic cough.

Clinically, there are some patients with underlying chronic cough etiology, but the cough has no obvious relief after targeted treatment. This cough is called refractory chronic cough. 

Treatment method: 

• The neuromodulator drug gabapentin is effective in the treatment of refractory chronic cough. It can also choose other drugs such as baclofen, amitriptyline, pregabalin, and carbamazepine.
• Patients with refractory chronic cough can use aerosol inhalation of lidocaine to achieve a certain temporary relief effect.