Can Cough Be Caused by Asthma?

Quick Answer

Yes, asthma can cause coughing. In fact, coughing is one of the most common symptoms of asthma. When asthma is the cause, the cough is often persistent, dry, and may worsen at night or with physical activity. This type of cough is sometimes called cough-variant asthma, where coughing is the main or only symptom.

How Asthma Causes Cough

Asthma is a chronic condition that affects the airways in your lungs. When exposed to triggers like allergens, cold air, or exercise, the airways become inflamed and narrow. This inflammation and narrowing make it difficult for air to move in and out of the lungs, leading to symptoms like wheezing, shortness of breath, and coughing.

The cough in asthma is typically caused by:

• Airway inflammation: The lining of the airways becomes swollen and irritated, triggering the cough reflex.
• Mucus production: The inflamed airways produce excess mucus, which the body tries to clear through coughing.
• Bronchoconstriction: The muscles around the airways tighten, narrowing the passages and making it harder to breathe, which can also trigger coughing.

In some cases, coughing may be the only noticeable symptom, especially in a condition known as cough-variant asthma. This form of asthma is often underdiagnosed because people may not associate their cough with asthma, particularly if they don’t experience wheezing or shortness of breath.

Other Symptoms of Asthma

While coughing can be a standalone symptom, asthma often presents with other signs, including:

• Wheezing: A high-pitched whistling sound when breathing, especially during exhalation.
• Shortness of breath: Difficulty breathing or feeling out of breath, even during light activities.
• Chest tightness: A feeling of pressure or squeezing in the chest.
• Increased mucus production: Excess phlegm or mucus, which may be clear, white, or yellow.

These symptoms can vary in severity and may worsen at night or early in the morning. They can also be triggered by specific factors like exercise, cold air, allergens (e.g., pollen, dust mites), or respiratory infections.

How Common Is This?

Coughing is a very common symptom of asthma. According to the Centers for Disease Control and Prevention (CDC), approximately 25 million Americans have asthma, and coughing is reported in the majority of cases. In cough-variant asthma, which accounts for about 30% of asthma cases, coughing is the primary or only symptom. This form is particularly common in children but can occur in adults as well.

A study published in the Journal of Asthma found that chronic cough is one of the most frequent reasons people seek medical attention for respiratory issues, and asthma is a leading cause of chronic cough in both children and adults.

Differentiating From Other Causes

Not all coughs are caused by asthma. To determine if asthma is the likely cause, consider the following:

Characteristics of an Asthma-Related Cough:

• Dry or non-productive: The cough doesn’t produce much mucus or phlegm.
• Worsens at night: Coughing often disrupts sleep or occurs early in the morning.
• Triggered by specific factors: Coughing may start or worsen with exercise, exposure to cold air, allergens, or respiratory infections.
• Associated with other asthma symptoms: Wheezing, shortness of breath, or chest tightness may accompany the cough.
• Persistent: The cough lasts for weeks or months and doesn’t improve with typical cough remedies.

Other Possible Causes of Chronic Cough:

If your cough doesn’t fit the pattern above, it might be caused by something else, such as:

• Postnasal drip: Mucus dripping down the throat from the nose due to allergies or a cold.
• Gastroesophageal reflux disease (GERD): Stomach acid flowing back into the esophagus, irritating the throat.
• Chronic obstructive pulmonary disease (COPD): A group of lung diseases, including emphysema and chronic bronchitis, often caused by smoking.
• Respiratory infections: Such as bronchitis, pneumonia, or whooping cough (pertussis).
• Medications: Certain drugs, like ACE inhibitors (used for high blood pressure), can cause a chronic cough.
• Environmental irritants: Exposure to smoke, pollution, or chemical fumes.

Getting a Diagnosis

If you suspect your cough is due to asthma, it’s important to see a healthcare provider for a proper diagnosis. Here’s what to expect during the diagnostic process:

Medical History:

Your doctor will ask about your symptoms, including:

• When the cough started and how long it’s lasted.
• What triggers the cough (e.g., exercise, allergens, cold air).
• Whether the cough is worse at certain times of day.
• Any family history of asthma or allergies.
• Other symptoms like wheezing, shortness of breath, or chest tightness.

Physical Examination:

Your doctor will listen to your lungs with a stethoscope to check for wheezing or other abnormal sounds. They may also look for signs of allergies, such as swollen nasal passages or a runny nose.

Lung Function Tests:

These tests measure how well your lungs are working and are key to diagnosing asthma:

• Spirometry: You’ll breathe into a machine that measures how much air you can exhale and how quickly. This test can show if your airways are narrowed.
• Peak flow measurement: A simple test that measures how fast you can blow air out of your lungs. Lower readings can indicate asthma.
• Bronchoprovocation test: If your initial spirometry is normal, your doctor might have you inhale a substance (like methacholine) that can trigger asthma symptoms. If your lung function drops significantly, it suggests asthma.

Additional Tests:

In some cases, your doctor may recommend:

• Allergy testing: To identify triggers like pollen, dust mites, or pet dander.
• Chest X-ray or CT scan: To rule out other conditions like infections or structural issues in the lungs.
• Exhaled nitric oxide test: Measures the level of nitric oxide in your breath, which can indicate inflammation in your airways.

Treatment Options

If asthma is diagnosed, treating it effectively can reduce or eliminate coughing. Treatment typically involves a combination of medications and lifestyle changes.

Medications:

• Quick-relief (rescue) inhalers: These are short-acting bronchodilators, such as albuterol, that quickly open the airways during an asthma attack or flare-up. They provide rapid relief from coughing, wheezing, and shortness of breath.
• Long-term control medications: These are taken daily to reduce airway inflammation and prevent symptoms. They include:
  • Inhaled corticosteroids: Such as fluticasone or budesonide, which reduce inflammation.
  • Leukotriene modifiers: Like montelukast, which help control immune system responses.
  • Long-acting bronchodilators: Often used in combination with inhaled corticosteroids for better control.
  • Biologics: For severe asthma, these targeted therapies can help reduce inflammation.

Lifestyle and Home Remedies:

• Avoid triggers: Identify and avoid things that worsen your asthma, such as smoke, allergens, or cold air.
• Use a humidifier: Adding moisture to the air can help reduce coughing, especially at night.
• Stay hydrated: Drinking plenty of fluids can thin mucus and make it easier to clear.
• Exercise regularly: With your doctor’s approval, regular physical activity can improve lung function. Always use your inhaler as prescribed before exercise if you have exercise-induced asthma.
• Manage allergies: If allergies trigger your asthma, work with your doctor to control them with medications or allergy shots.

Action Plan:

Your doctor may provide an asthma action plan, which outlines:

• How to manage your asthma daily.
• How to recognize and handle worsening symptoms.
• When to seek emergency care.

When It's NOT Asthma

If your cough isn’t improving with asthma treatment, or if your symptoms don’t match the typical pattern of asthma, your doctor may consider other diagnoses. Some conditions that can mimic asthma include:

Common Alternatives:

• Chronic obstructive pulmonary disease (COPD): More common in smokers or former smokers, COPD causes persistent coughing, wheezing, and shortness of breath.
• Gastroesophageal reflux disease (GERD): Stomach acid irritating the esophagus or airways can cause a chronic cough, often worse at night or after eating.
• Postnasal drip: Allergies or sinus infections can cause mucus to drip down the throat, leading to a persistent cough.
• Vocal cord dysfunction (VCD): The vocal cords close abnormally during breathing, mimicking asthma symptoms like coughing and wheezing.
• Heart failure: In some cases, fluid buildup in the lungs due to heart problems can cause coughing and shortness of breath.

Less Common Causes:

• Lung infections: Tuberculosis, fungal infections, or persistent bacterial infections.
• Interstitial lung disease: A group of disorders that cause scarring of lung tissue.
• Lung cancer: Though less likely, a chronic cough can sometimes be a symptom of lung cancer, especially in smokers.

If your doctor suspects one of these conditions, they may order additional tests, such as imaging studies, blood tests, or refer you to a specialist.

When to See a Doctor

It’s important to seek medical attention if you experience any of the following:

Even if your symptoms aren’t severe, see your doctor if:

• Your cough disrupts your sleep or daily activities.
• You notice coughing fits triggered by exercise, allergens, or cold air.
• Over-the-counter cough medicines don’t help.
• You have a history of asthma or allergies in your family.

Early diagnosis and treatment can help manage asthma effectively and prevent complications like severe asthma attacks or long-term lung damage.

Key Takeaways

• Yes, asthma can cause coughing. It’s one of the most common symptoms, and in some cases, it may be the only symptom (cough-variant asthma).
• Asthma-related coughs are usually dry, persistent, and worse at night or with triggers like exercise or allergens.
• Other asthma symptoms include wheezing, shortness of breath, and chest tightness. Not everyone experiences all of these.
• Diagnosis involves a medical history, physical exam, and lung function tests like spirometry. Allergy testing may also be recommended.
• Treatment includes quick-relief inhalers for sudden symptoms and long-term medications to control inflammation. Avoiding triggers is also crucial.
• Not all coughs are due to asthma. Other conditions like GERD, postnasal drip, COPD, or infections can cause similar symptoms.
• See a doctor if your cough is persistent, severe, or accompanied by trouble breathing, wheezing, or other concerning symptoms.
• Early intervention can improve your quality of life and reduce the risk of complications.

If you suspect your cough is related to asthma, don’t hesitate to reach out to a healthcare provider. With the right diagnosis and treatment plan, you can manage your symptoms and breathe easier.

Sources and Further Reading:

• Mayo Clinic: Asthma
• CDC: Asthma FAQs
• NIH: Asthma
• WHO: Asthma Fact Sheet
• Cleveland Clinic: Asthma