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Acute Bronchitis


Sanjay Sethi

, MD, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences

Reviewed/Revised May 2023
Topic Resources

Acute bronchitis is inflammation of the windpipe (trachea) and the airways that branch off the trachea (bronchi) caused by infection.

  • Acute bronchitis is usually caused by a viral upper respiratory tract infection.

  • Symptoms are a cough that may or may not produce mucus (sputum).

  • The diagnosis is based primarily on symptoms.

  • Treatments, such as medications to reduce fever and cough, may be used to make the person more comfortable until the episode ends.

  • Antibiotics are rarely needed.

Bronchitis can be either

  • Acute

  • Chronic

Acute bronchitis usually lasts days to a few weeks. Bronchitis that lasts for months or years is usually classified as chronic bronchitis Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease is persistent narrowing (blocking, or obstruction) of the airways occurring with emphysema, chronic obstructive bronchitis, or both disorders. Cigarette... read more Chronic Obstructive Pulmonary Disease (COPD) . When people say "bronchitis," they usually mean acute bronchitis, and only acute bronchitis is discussed here.

Causes of Acute Bronchitis

Acute bronchitis is caused by infection due to

  • Viruses (most common)

  • Bacteria

Understanding Bronchitis


Bronchitis occurs most often during the winter.


Symptoms of Acute Bronchitis

Infections causing acute bronchitis typically begin with the symptoms of a common cold: runny nose, sore throat, and fatigue. In addition, in people with COVID-19, fever, muscle aches, gastrointestinal symptoms, and loss of smell and taste are more common.

After several days, cough begins (usually dry at first). People may cough up small amounts of thin, white mucus. This mucus often changes from white to green or yellow and becomes thicker. The color change does not indicate a bacterial infection. Color change means only that cells associated with inflammation have moved into the airway and are coloring the sputum.

Did You Know...

  • Coughing up yellow or green-colored sputum does not mean the infection is caused by bacteria.

Diagnosis of Acute Bronchitis

  • A doctor's evaluation

  • Sometimes a chest x-ray

Doctors usually make a diagnosis of acute bronchitis based on the symptoms. Doctors may do a chest x-ray to look for pneumonia Overview of Pneumonia Pneumonia is an infection of the small air sacs of the lungs (alveoli) and the tissues around them. Pneumonia is one of the most common causes of death worldwide. Often, pneumonia is the final... read more Overview of Pneumonia if they hear congestion in the lungs, or if people have high or prolonged fever or shortness of breath.

Doctors rarely do tests to find the cause of acute bronchitis, and blood tests are not helpful. However, testing for SARS-CoV2 may be done. Also, if a cough persists for more than 8 weeks, a chest x-ray is done to make sure that pneumonia has not developed or a different lung disease is not causing the cough.

Treatment of Acute Bronchitis

  • Treatments to relieve symptoms

People may take acetaminophen or ibuprofen to reduce fever and general feelings of illness and should drink plenty of fluid.

Antibiotics do not help viral bronchitis. Since most acute bronchitis is viral, doctors give antibiotics only when the infection is clearly caused by bacteria (for example, during an outbreak). When an antibiotic is used, doctors typically give a medication such as azithromycin or clarithromycin. Sometimes doctors prescribe antibiotics but recommend that they be used only if symptoms persist.

Did You Know...

  • Acute bronchitis is usually treated best without using an antibiotic.

People who are wheezing may benefit from inhaled bronchodilators Treatment Treatment for a few days; however, side effects such as tremor, nervousness, and shaking can occur.

Cough medicines Cough suppressants Cough is a sudden, forceful expulsion of air from the lungs. It is one of the most common reasons people see a doctor. The function of a cough is to clear material from the airways and to protect... read more can be used to suppress a cough that is distressing or interferes with sleep. However, the degree of effectiveness of these medications is not clear. Expectorants are over-the-counter medications that may help thin secretions and make them easier to cough up, but whether this measure is helpful is not clear. Cough suppressants and expectorants are usually not recommended in young children (see also Cough in Children Cough in Children Cough helps clear materials from the airways and prevent them from going to the lungs. The materials may be particles that have been inhaled or substances from the lungs and/or airways. Most... read more ).

Drugs Mentioned In This Article

Generic Name Select Brand Names
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Apra, Children's Acetaminophen, Children's Pain & Fever , Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Midol, Midol Cramps and Body Aches, Motrin, Motrin Children's, Motrin IB, Motrin Infants', Motrin Junior Strength, Motrin Migraine Pain, PediaCare Children's Pain Reliever/Fever Reducer IB, PediaCare Infants' Pain Reliever/Fever Reducer IB, Samson-8
Azasite, Zithromax, Zithromax Powder, Zithromax Single-Dose , Zithromax Tri-Pak, Zithromax Z-Pak, Zmax, Zmax Pediatric
Biaxin, Biaxin XL
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