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Published on: 2/28/2026

Still Coughing? Why Acute Bronchitis Inflames Lungs & Medical Steps

Acute bronchitis is a short term inflammation of the bronchial tubes that often follows a viral infection, causing swelling, excess mucus, and airway sensitivity so a cough can last 2 to 3 weeks. Most people improve with rest, fluids, OTC cough and pain relief, humidified air, avoiding smoke, and sometimes a short acting inhaler if wheezing; antibiotics are usually not needed.

There are several factors to consider; see below to understand more, including when to seek care for fever over 100.4 F for days, trouble breathing at rest, chest pain not from coughing, coughing up blood, symptoms beyond 3 to 4 weeks, or if you are older, smoke, or have asthma, COPD, heart disease, or a weak immune system.

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Explanation

Still Coughing? Why Acute Bronchitis Inflames the Lungs & What to Do Next

A lingering cough can be frustrating. If you're still coughing weeks after a cold, acute bronchitis may be the reason. This common respiratory condition inflames the bronchial tubes—the airways that carry air into your lungs—leading to cough, mucus, and chest discomfort.

Most cases improve on their own. But understanding what's happening inside your lungs and knowing when to seek medical care can help you recover safely and avoid complications.


What Is Acute Bronchitis?

Acute bronchitis is a short-term inflammation of the bronchial tubes. These airways normally produce a small amount of mucus to trap dust and germs. When they become irritated or infected, they swell and produce excess mucus. This triggers coughing as your body tries to clear the airways.

Acute bronchitis is different from chronic bronchitis:

  • Acute bronchitis: Short-term, usually follows a viral infection.
  • Chronic bronchitis: Long-term condition (lasting at least 3 months for 2 consecutive years), often related to smoking or long-term irritant exposure.

Most cases of acute bronchitis are caused by viruses—the same ones that cause colds and the flu.


Why Acute Bronchitis Causes So Much Coughing

The hallmark symptom of acute bronchitis is a persistent cough. Here's why it lingers:

  1. Airway inflammation
    When viruses infect the bronchial tubes, your immune system responds with inflammation. The swelling narrows the airways, making breathing feel tight or uncomfortable.

  2. Excess mucus production
    Inflamed airways produce more mucus than usual. This mucus can:

    • Trigger frequent coughing
    • Cause chest congestion
    • Change color (clear, white, yellow, or green)
  3. Airway sensitivity
    Even after the infection clears, the airways may remain sensitive for weeks. Cold air, exercise, or irritants can trigger more coughing.

A cough from acute bronchitis often lasts 2 to 3 weeks, and sometimes longer. That does not automatically mean something is seriously wrong—but it should gradually improve.


Common Symptoms of Acute Bronchitis

Symptoms often begin like a common cold and then progress.

Typical signs include:

  • Persistent cough (with or without mucus)
  • Chest tightness or discomfort
  • Mild shortness of breath
  • Wheezing
  • Fatigue
  • Low-grade fever
  • Sore throat

It's important to note: colored mucus does not automatically mean a bacterial infection. Viral infections commonly produce yellow or green mucus as part of the immune response.


What Causes Acute Bronchitis?

In most cases, acute bronchitis is caused by viruses such as:

  • Influenza (flu)
  • Rhinovirus (common cold)
  • Respiratory syncytial virus (RSV)
  • Coronavirus strains

Less commonly, bacteria may be involved.

Non-infectious triggers can also inflame the airways:

  • Tobacco smoke
  • Air pollution
  • Dust
  • Chemical fumes
  • Vaping

Smoking significantly increases both the risk and severity of acute bronchitis.


How Is Acute Bronchitis Diagnosed?

Doctors typically diagnose acute bronchitis based on:

  • Your symptoms
  • Medical history
  • Physical exam
  • Listening to your lungs with a stethoscope

In most healthy adults, testing is not needed.

However, your doctor may recommend further testing if they suspect:

  • Pneumonia
  • Asthma
  • Chronic obstructive pulmonary disease (COPD)
  • Whooping cough

Chest X-rays are usually only done if pneumonia is suspected.

If you're experiencing these symptoms and want personalized insight into what might be causing them, you can use Ubie's free AI-powered Acute / Chronic Tracheitis / Bronchitis Symptom Checker to get a clearer picture in just minutes.


Medical Steps for Treating Acute Bronchitis

Because most cases are viral, antibiotics are not usually recommended. Overuse of antibiotics can lead to resistance and side effects without helping recovery.

Instead, treatment focuses on symptom relief.

1. Rest and Hydration

  • Drink plenty of fluids to thin mucus.
  • Rest to allow your immune system to recover.

2. Over-the-Counter Relief

Depending on your symptoms, a doctor may recommend:

  • Cough suppressants (for dry, disruptive cough)
  • Expectorants (to help loosen mucus)
  • Pain relievers such as acetaminophen or ibuprofen
  • Throat lozenges

Always follow dosing instructions carefully.

3. Inhalers (If Needed)

If wheezing or airway tightness is significant, a doctor may prescribe:

  • A short-acting bronchodilator inhaler

This is more common in people with asthma or reactive airways.

4. Avoid Irritants

  • Do not smoke.
  • Avoid secondhand smoke.
  • Stay away from strong fumes or air pollution.

5. Humidified Air

A cool-mist humidifier may ease coughing and soothe irritated airways.


When to See a Doctor

Most cases of acute bronchitis improve without complications. However, some symptoms require medical attention.

Speak to a doctor promptly if you experience:

  • Fever above 100.4°F (38°C) lasting more than a few days
  • Shortness of breath at rest
  • Chest pain unrelated to coughing
  • Cough lasting more than 3–4 weeks
  • Coughing up blood
  • Underlying lung or heart disease
  • Weakened immune system

These could signal pneumonia or another serious condition that requires treatment.

If symptoms feel severe, sudden, or life-threatening—such as difficulty breathing—seek urgent medical care immediately.


How Long Does Recovery Take?

For most healthy adults:

  • Fever and body aches improve within a few days.
  • Cough typically lasts 2–3 weeks.
  • Mild airway sensitivity may last up to 4 weeks.

If your cough is improving—even slowly—that's usually a good sign.

However, if your cough worsens instead of improving, it's important to consult a healthcare professional.


Who Is at Higher Risk for Complications?

Certain groups may experience more severe illness:

  • Adults over 65
  • Smokers
  • People with asthma or COPD
  • Those with weakened immune systems
  • Individuals with heart disease

In these cases, closer medical monitoring is often appropriate.


Can Acute Bronchitis Turn Into Something More Serious?

In some cases, acute bronchitis can lead to:

  • Pneumonia
  • Asthma flare-ups
  • Secondary bacterial infections

While uncommon in healthy individuals, complications are possible—especially if symptoms are ignored or if underlying conditions exist.

That's why it's important not to dismiss severe or prolonged symptoms.


Preventing Acute Bronchitis

You can lower your risk by:

  • Washing hands regularly
  • Avoiding close contact with sick individuals
  • Getting annual flu vaccination
  • Avoiding smoking and vaping
  • Wearing a mask in high-risk environments if appropriate
  • Managing chronic lung conditions properly

Good lung health habits go a long way in preventing recurrent inflammation.


The Bottom Line

Acute bronchitis is common and usually temporary, but it can feel disruptive and exhausting. The persistent cough happens because inflamed airways produce excess mucus and remain sensitive even after infection clears.

The good news: most people recover fully with rest, fluids, and supportive care.

Still, don't ignore warning signs. If symptoms are severe, worsening, or lasting longer than expected, speak to a doctor. Early evaluation can rule out pneumonia or other serious conditions.

If you're unsure what your symptoms might mean, consider using a free online symptom check for Acute / Chronic Tracheitis / Bronchitis to guide your next steps.

Your lungs are resilient—but they deserve attention when something doesn't feel right. When in doubt, consult a qualified healthcare professional to ensure you're on the safest path to recovery.

(References)

  • * Smith, S. M., & Fahey, T. (2018). Acute bronchitis: an update on diagnosis and treatment. *American Family Physician*, *97*(11), 695–701. https://pubmed.ncbi.nlm.nih.gov/29890069/

  • * Kligler, B., & Gold, A. (2020). Acute bronchitis: diagnosis and treatment. *BMJ*, *369*, m1789. https://pubmed.ncbi.nlm.nih.gov/32414728/

  • * Dicpinigaitis, P. V. (2022). Cough and acute bronchitis: an updated narrative review. *Pulmonary Pharmacology & Therapeutics*, *73*, 102123. https://pubmed.ncbi.nlm.nih.gov/36319323/

  • * Patel, A. N., & Kumar, S. (2023). Acute Bronchitis in Adults. *The New England Journal of Medicine*, *389*(16), 1500–1509. https://pubmed.ncbi.nlm.nih.gov/37851609/

  • * Marley, J. E., & Mandell, L. A. (2019). Viral acute bronchitis in adults. *Current Opinion in Infectious Diseases*, *32*(6), 562–567. https://pubmed.ncbi.nlm.nih.gov/31609710/

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