What causes bronchitis?

Matthew Varner, DO

Critical Care Medicine

Whenever respiratory viruses like influenza, or bacterial illnesses like whooping cough, appear, bronchitis is often on their heels. Bronchitis happens when the bronchial tubes, which carry air into the lungs, become irritated. What causes bronchitis? Is it an inevitable result of a respiratory illness?

Critical care and pulmonology specialist Matthew Varner, DO, answered questions about what causes bronchitis, how it’s treated and more.

What is bronchitis?

“When the bronchial tubes become inflamed, they produce extra mucus. Thanks to the inflammation and the mucus, it becomes more difficult to breathe and causes serious discomfort,” said Dr. Varner.

There are two kinds of bronchitis: acute and chronic. Acute bronchitis is a short-term problem, generally caused by a respiratory infection, and it goes away within a few weeks. Chronic bronchitis, on the other hand, is much longer lasting, and usually happens as a result of smoking or as part of the ongoing medical condition chronic obstructive pulmonary disease, or COPD.

What causes bronchitis?

“Acute bronchitis is usually caused as a result of viruses like influenza or the common cold,” said Dr. Varner. “Sometimes, bacteria can cause it. One example would be the germs that cause whooping cough. Irritants like dust, fumes or strong chemicals can also cause enough airway irritation to result in bronchitis, too.”

Chronic bronchitis, on the other hand, is most often a result of smoking. Cigarette smoke irritates and damages airways over time, creating high risk for medical conditions like COPD or emphysema as well as bronchitis.

Other causes of chronic bronchitis are air pollution, secondhand smoke, workplace hazards like coal dust or chemical fumes, repeated infections with acute bronchitis and, in rare cases, a genetic condition called Alpha-1 antitrypsin deficiency.

What are the symptoms of bronchitis?

“Usually, the first thing we hear from a patient dealing with bronchitis is that they have a cough that just won’t go away,” said Dr. Varner. “Often this lingering cough is productive, which means they’re coughing up mucus, which could be clear, yellow, green or even have a little blood in it.”

Other common bronchitis symptoms are soreness or discomfort thanks to all the coughing, shortness of breath or wheezing, or a feeling very low on energy or fatigued. Some people with bronchitis report a slight fever or feeling chills when their bronchitis is caused by an infection.

Finally, a sore throat or runny nose is also commonly seen with bronchitis.

With chronic bronchitis, Dr. Varner noted that many of the symptoms on the surface look the same but happen over a much longer period of time, are more severe and don’t respond to over-the-counter medications.

Symptoms of chronic bronchitis include:

• A cough that sticks around for at least three months a year, for two years in a row

• Mucus is usually thick and can be yellow or green
• Shortness of breath, especially when moving around
• Repeated respiratory infections
• Wheezing or tightness in the chest
• Feeling very tired and not able to do as much physically

Can you treat bronchitis at home?

“Acute bronchitis can usually be handled at home, especially if it’s caused by a virus,” said Dr. Varner. “Antibiotics don’t help with viruses, and taking antibiotics when you have a viral infection, unfortunately, only worsens our ongoing problem with increasing antibiotic resistance.”

Dr. Varner offered the following tips on how to treat bronchitis at home:

• Rest up: Let your body recover, especially if you’re feeling feverish or tired.
• Drink lots of fluids: Water, broth or herbal teas can help thin out mucus and soothe your throat. Skip sugary or caffeinated drinks if they make you feel worse.
• Use a humidifier: Moist air can help loosen mucus and make coughing easier. Just clean the humidifier often to avoid mold.
• Try over-the-counter (OTC) medicines:
  • Cough medicines: If you have a dry cough with no mucus, something like dextromethorphan can help, but don’t overdo it – coughing helps clear your lungs.
  • Mucus thinners: Medicines like guaifenesin can help loosen mucus.
  • Pain relievers: Ibuprofen or acetaminophen can help with fever, sore throat or aches.
• Avoid irritants: Stay away from smoke, dust or strong smells that make your symptoms worse.
• Use warm compresses or steam: Breathing in steam or putting a warm compress on your chest can help loosen mucus.
• Try honey: Mix it with warm water or tea to soothe your throat and calm your cough. However, do not give honey to kids under 1 year old, as it can put them at risk for the foodborne illness botulism.

Chronic bronchitis requires long-term care, most often with a doctor’s help. Lifestyle changes like quitting smoking, using a humidifier and avoiding outdoor or indoor air pollution and other irritants can absolutely help reduce symptoms.

How long does bronchitis last and is it contagious?

“Acute bronchitis usually lasts between one to three weeks, but the cough might hang around for four to six weeks while your airways are healing,” said Dr. Varner. “Usually, people feel better in a week to 10 days but still feel a little tired or have a mild cough.”

Chronic bronchitis, which can stick around for months or years with ongoing symptoms, often involves periods where symptoms flare up from time to time after infections or exposure to irritants. Some of those flare-ups might require a doctor’s visit and prescribed treatment.

Is bronchitis contagious?

“Acute bronchitis can be contagious if it’s caused by a virus or bacteria,” said Dr. Varner. “Illnesses like the cold, flu or whooping cough spread through coughing, sneezing or close contact.”

To keep from getting sick, wash your hands, cover your mouth when you cough and don’t share utensils. Consider wearing a mask when out and about to help prevent spreading the illness around as well.

Acute bronchitis or chronic bronchitis caused by irritants like smoking, dust or fumes is not contagious.

When should you see a doctor for bronchitis?

“Most cases of acute bronchitis get better on their own,” said Dr. Varner. “There are some circumstances, however, where you should see a doctor.”

Schedule an appointment with your doctor if your symptoms last more than three weeks and include any of the following symptoms:

• Your cough is getting worse or keeps you up at night.
• You have a high fever (over 100.4°F or 38°C) for more than three days.
• You cough up blood or see blood in your mucus.
• You’re short of breath, wheezing a lot or have chest pain.
• You have other health problems like asthma, COPD, heart disease or a weak immune system.
• You think you might have whooping cough (lots of violent coughing, especially in kids). Vaccination with the DTap (given to infants and small children) or Tdap (given to adolescents and adults) provides strong protection against whooping cough.
• Your symptoms keep coming back or don’t get better with home care.

“For chronic bronchitis, you’ll need regular check-ups with your doctor to manage it and adjust treatments,” said Dr. Varner. “If your symptoms get worse, like more shortness of breath or signs of infection, get help right away”

What’s the difference between bronchitis and pneumonia?

“While both bronchitis and pneumonia cause some of the same symptoms, they affect different parts of your lungs,” said Dr. Varner. “On top of that, pneumonia can become very serious or even dangerous.”

While bronchitis is uncomfortable or even sometimes painful and lingering, pneumonia is considered a more serious medical condition. In pneumonia, the tiny air sacs inside the lungs become infected or inflamed, suppressing the amount of oxygen that can get into the blood. Pneumonia usually has symptoms like a high fever, chills, a cough with thick or bloody mucus, shortness of breath or chest paint hat gets worse when you cough or breathe deeply.

“Doctors usually need to do a chest X-ray or tests to figure out what is causing your pneumonia, and treatment includes options like antibiotics for bacterial pneumonia, antivirals for viral pneumonia or antifungals for fungal pneumonia,” said Dr. Varner.

In some cases, hospitalization for oxygen or IV fluids is required. Pneumonia may result in serious problems like lung infections, trouble breathing or even sepsis, a potentially fatal body-wide infection.

“The biggest difference between bronchitis and pneumonia is that bronchitis involves irritated airways and is usually milder, while pneumonia is an infection in the air sacs and is usually much more serious,” said Dr. Varner.

Pneumonia usually requires stronger treatment than bronchitis and is much more likely to result in needing hospital care. While both may be contagious, pneumonia is riskier and may lead to more complications.

Since both conditions have similar initial symptoms, it’s important to speak with your doctor if you’re experiencing shortness of breath due to irritants or illness and to keep an eye out for other symptoms.