Persistent Dry Cough: Causes from Allergies to Acid Reflux

At-a-Glance

• A dry cough lasting more than 3 weeks is considered chronic and warrants medical evaluation
• Common causes include post-nasal drip, asthma, acid reflux, and medication side effects
• ACE inhibitor blood pressure medications cause chronic dry cough in up to 20% of users
• Most cases are not serious but can significantly impact quality of life
• Treatment focuses on identifying and addressing the underlying cause

What It Feels Like

A persistent dry cough is a cough that produces little to no mucus (phlegm) and lasts for weeks or months. Unlike a productive "wet" cough, a dry cough feels like an irritation or tickle in the throat that triggers the cough reflex.

Common descriptions include:

• Tickling or scratchy sensation in the throat
• Hacking or barking cough
• Cough that worsens at night or when lying down
• Feeling like you need to clear your throat constantly
• Chest tightness or discomfort from coughing
• Cough triggered by talking, laughing, or deep breathing
• Exhaustion from frequent coughing episodes

The cough may be worse at certain times of day or triggered by specific factors like cold air, exercise, or lying down.

Common Causes

Post-Nasal Drip (Upper Airway Cough Syndrome)

Post-nasal drip occurs when excess mucus from the nose and sinuses drips down the back of the throat, irritating the airways and triggering a cough reflex.

Signs it might be post-nasal drip:

• Sensation of mucus dripping down the back of throat
• Frequent throat clearing
• Cough worse at night or upon waking
• Nasal congestion or runny nose
• Sore or scratchy throat
• Bad breath

Common causes of post-nasal drip:

• Allergies (seasonal or year-round)
• Sinus infections
• Common cold
• Deviated septum
• Dry air

What helps:

• Saline nasal rinses or sprays
• Antihistamines for allergies
• Decongestants (short-term use)
• Nasal corticosteroid sprays
• Humidifier in bedroom
• Stay hydrated
• Elevate head while sleeping

Asthma (Cough-Variant Asthma)

Some people with asthma experience chronic cough as their primary or only symptom, without the typical wheezing or shortness of breath.

Signs it might be asthma:

• Cough triggered by exercise, cold air, or allergens
• Cough worse at night
• Chest tightness
• Shortness of breath with exertion
• Family history of asthma or allergies
• Symptoms improve with asthma medications

What helps:

• Inhaled corticosteroids (controller medications)
• Bronchodilators (rescue inhalers)
• Avoid triggers (smoke, allergens, cold air)
• Allergy management
• Regular follow-up with doctor

Gastroesophageal Reflux Disease (GERD)

Acid reflux can irritate the throat and airways, causing a chronic dry cough. This is often overlooked because many people with reflux-related cough don't have typical heartburn symptoms.

Signs it might be GERD:

• Cough worse after eating or when lying down
• Sour taste in mouth
• Hoarseness or voice changes
• Sensation of lump in throat
• May or may not have heartburn
• Cough improves with acid-reducing medications

What helps:

• Avoid trigger foods (spicy, fatty, acidic foods, chocolate, caffeine)
• Eat smaller, more frequent meals
• Don't eat within 3 hours of bedtime
• Elevate head of bed 6-8 inches
• Lose weight if overweight
• Proton pump inhibitors (PPIs) or H2 blockers
• Antacids for symptom relief

ACE Inhibitor Medications

ACE inhibitors, commonly prescribed for high blood pressure and heart failure, cause a persistent dry cough in 10-20% of users.

Common ACE inhibitors:

• Lisinopril (Prinivil, Zestril)
• Enalapril (Vasotec)
• Ramipril (Altace)
• Benazepril (Lotensin)

Signs it's medication-related:

• Cough started within weeks to months of starting medication
• Dry, tickling cough
• No other symptoms
• Cough persists despite other treatments

What helps:

• Discuss with your doctor about switching to an ARB (angiotensin receptor blocker)
• Never stop blood pressure medication without medical guidance
• Cough typically resolves within 1-4 weeks of stopping ACE inhibitor

Chronic Bronchitis

Chronic bronchitis, often related to smoking, causes inflammation of the airways and persistent cough.

Signs it might be chronic bronchitis:

• Cough most days for at least 3 months per year, for 2 consecutive years
• History of smoking or exposure to irritants
• Cough may be dry or productive
• Shortness of breath
• Wheezing
• Frequent respiratory infections

What helps:

• Quit smoking (most important)
• Avoid air pollutants and irritants
• Bronchodilators
• Inhaled corticosteroids
• Pulmonary rehabilitation
• Vaccinations (flu, pneumonia)

Environmental Irritants

Exposure to irritants can cause chronic cough without underlying disease.

Common irritants:

• Cigarette smoke (including secondhand smoke)
• Air pollution
• Strong perfumes or chemicals
• Dust and mold
• Pet dander
• Occupational exposures

What helps:

• Identify and avoid triggers
• Improve indoor air quality
• Use air purifiers
• Wear mask if exposure unavoidable
• Ensure proper ventilation

Less Common but Serious Causes

Lung Cancer

While rare, persistent cough can be a symptom of lung cancer, especially in smokers or former smokers.

Warning signs:

• Cough that changes in character
• Coughing up blood
• Unintentional weight loss
• Chest pain
• Shortness of breath
• Hoarseness

Action: See a doctor promptly, especially if you smoke or have smoked.

Interstitial Lung Disease

A group of disorders causing lung scarring can present with chronic dry cough.

Warning signs:

• Progressive shortness of breath
• Dry cough
• Fatigue
• Unexplained weight loss
• Clubbing of fingers

Action: Medical evaluation with chest imaging and pulmonary function tests.

Heart Failure

Fluid backing up into the lungs from heart failure can cause cough, especially when lying down.

Warning signs:

• Shortness of breath, especially when lying flat
• Swelling in legs, ankles, or feet
• Fatigue
• Rapid weight gain
• Cough that produces pink, frothy sputum

Action: Seek medical evaluation promptly.

When to See a Doctor

Schedule a doctor's appointment if:

• Cough lasts more than 3 weeks
• Cough is worsening or changing
• You're coughing up thick, discolored mucus
• You have fever, night sweats, or unintentional weight loss
• You're a smoker or former smoker with new or changing cough
• Cough interferes with sleep or daily activities
• You have other concerning symptoms

Diagnosis

Your doctor may perform:

• Medical history: Including medications, smoking history, exposures
• Physical examination: Listening to lungs, examining throat
• Chest X-ray: To visualize lungs and rule out serious conditions
• Spirometry: Breathing test to check for asthma or COPD
• Allergy testing: If allergies suspected
• pH monitoring: If GERD suspected
• CT scan: For more detailed lung imaging if needed
• Bronchoscopy: Direct visualization of airways in some cases

Treatment Approaches

Treatment depends on the underlying cause:

For Post-Nasal Drip

• Antihistamines (loratadine, cetirizine)
• Nasal corticosteroid sprays (fluticasone, mometasone)
• Decongestants (short-term)
• Saline nasal irrigation

For Asthma

• Inhaled corticosteroids (fluticasone, budesonide)
• Long-acting bronchodilators
• Leukotriene modifiers (montelukast)
• Avoid triggers

For GERD

• Proton pump inhibitors (omeprazole, esomeprazole)
• H2 blockers (famotidine, ranitidine)
• Lifestyle modifications
• Dietary changes

For ACE Inhibitor Cough

• Switch to ARB medication
• Alternative blood pressure medication

Symptomatic Relief

• Cough suppressants (dextromethorphan) for nighttime use
• Throat lozenges
• Honey (1-2 teaspoons)
• Humidifier
• Stay hydrated

Self-Care Strategies

General Measures

• Stay hydrated: Drink plenty of water to thin mucus
• Use humidifier: Especially in dry climates or during winter
• Avoid irritants: Smoke, strong perfumes, chemicals
• Honey: Natural cough suppressant (1-2 teaspoons)
• Elevate head: When sleeping, if cough worsens lying down
• Warm liquids: Tea with honey, warm water with lemon

Lifestyle Modifications

• Quit smoking: Most important if you smoke
• Manage allergies: Identify and avoid allergens
• Control GERD: Dietary changes, weight loss, avoid late meals
• Improve air quality: Air purifiers, regular cleaning
• Stress management: Stress can worsen cough

When to Use Cough Suppressants

• Nighttime, to allow sleep
• Dry, non-productive cough
• After ruling out serious causes
• Short-term use only
• Avoid if cough is productive (bringing up mucus)

Frequently Asked Questions

The Bottom Line

A persistent dry cough is frustrating and can significantly impact quality of life, but it's usually caused by treatable conditions rather than serious disease. The most common culprits—post-nasal drip, asthma, and acid reflux—often respond well to targeted treatment once identified.

The key is determining the underlying cause through medical evaluation. While over-the-counter cough suppressants can provide temporary relief, addressing the root cause is essential for long-term resolution.

Don't ignore a cough that lasts more than 3 weeks. Early evaluation can identify treatable causes and, in rare cases, detect serious conditions when they're most manageable.

Remember: This information is educational and doesn't replace professional medical advice. If you have a persistent cough, consult a healthcare provider for proper diagnosis and treatment.