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Acute Bronchitis


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Last full review/revision Sep 2019
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What is acute bronchitis?

Your bronchi are the tubes that carry air into your lungs. Bronchitis is when the bronchi become swollen and irritated.

Acute bronchitis starts suddenly, usually over a few days. Acute bronchitis differs from chronic bronchitis. In chronic bronchitis, your airways have been inflamed (swollen) for years. Chronic bronchitis occurs in people with lung problems such as COPD or cystic fibrosis.

  • Acute bronchitis is caused by an infection, such as a cold

  • Your airways swell and make mucus, which makes you cough more

  • Your cough can last for several weeks

  • You’re more likely to get acute bronchitis in the winter

If you're a healthy person without any lung disease, acute bronchitis isn't dangerous. If you have lung disease, acute bronchitis may make your lung symptoms worse. For example, if you have asthma, you may start wheezing.

Inside the Lungs and Airways

Inside the Lungs and Airways

Understanding Bronchitis

Understanding Bronchitis

What causes acute bronchitis?

Acute bronchitis is nearly always caused by a virus, such as the common cold or flu (influenza) virus. It can also be caused by certain bacteria.

What are the symptoms of acute bronchitis?

If you have acute bronchitis, your symptoms may last from a few days to a few weeks or more.

At first, you may have cold or flu symptoms such as:

  • Runny nose

  • Sore throat

  • Tiredness, chills, sore muscles

  • Slight fever (100° to 101° F or 37.5° to 38° C)

These symptoms usually last 3 to 5 days.

Then you get a cough. The cough:

  • Usually doesn't produce mucus at first

  • Later may produce clear, yellow, green, or sometimes even bloody mucus

  • May make your chest hurt when you cough or breathe deeply

  • Often lasts 2 to 3 weeks and sometimes even longer

You may also have wheezing, even if you don't have asthma.

How can doctors tell if I have acute bronchitis?

Doctors can usually tell if you have acute bronchitis just by asking about your symptoms and examining your lungs. However, the symptoms of acute bronchitis can be similar to mild pneumonia. Pneumonia is infection of your lung tissue and is more dangerous than bronchitis. Doctors may do a chest x-ray to look for pneumonia if you:

  • Are elderly

  • Are very sick

  • Have a high fever and rapid breathing

  • Have chronic lung disease

How is acute bronchitis treated?

Your doctor will treat your symptoms:

  • If you have fever or chest pain from coughing, you can take over-the-counter medicines such as acetaminophen or ibuprofen

  • If you have wheezing, your doctor may prescribe an inhaler (a little spray bottle with medicine that you breathe in)

Cough medicines almost never make you feel better, but some can help a little at night if your cough keeps you from sleeping.

Doctors used to think antibiotics would help if your mucus was thick and yellow. Now they know antibiotics don't work in acute bronchitis except in the rare cases when it is caused by bacteria.

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