Acute Bronchitis

Reviewed on 11/14/2022

What to Know About Acute Bronchitis

Picture of a woman coughing.
Acute bronchitis usually resolves on its own in about 2-3 weeks.
  • Acute bronchitis describes the inflammation of the bronchi usually caused by a viral infection, although bacteria and chemicals also may cause acute bronchitis. Bronchiolitis is a term that describes inflammation of the smaller bronchi referred to as bronchioles. In infants, this is usually caused by respiratory syncytial viruses (RSV) and affects the small bronchi and bronchioles more than the large ones. In adults, other viruses as well as some bacteria can cause bronchiolitis and often manifest as a persistent cough at times productive of small plugs of mucus. Acute bronchitis is a cough that begins suddenly usually due to a viral infection involving the larger airways. Colds (also known as viral upper airway infections) often involve the throat (pharyngitis) and nasal passages and at times the larynx (resulting in a diminished hoarse voice, also known as laryngitis). Symptoms can include a runny nose, nasal stuffiness, and sore throat. Croup usually occurs in infants and young children and involves the voice box and upper large airways (the trachea and large bronchi).
  • Chronic bronchitis for research purposes is defined as a daily cough with sputum production for at least 3 months, 2 years in a row. Chronic bronchitis is a diagnosis usually made based on clinical findings of a long-term persistent cough usually associated with tobacco abuse. From a pathologic standpoint, characteristic microscopic findings involving inflammatory cells seen in airway tissue samples make the diagnosis. When referring to pulmonary function testing, a decrease in the ratio of the volume of airflow at 1 second when compared to total airflow is less than 70%. This confirms the presence of obstructive airway disease of which chronic bronchitis is one type. Certain findings can be seen in imaging studies (chest X-ray, and CT or MRI of the lungs) to suggest the presence of chronic bronchitis; usually, this involves the appearance of thickened tubes.
  • Signs and symptoms of acute bronchitis include: 
  • People with underlying lung diseases such as asthma or chronic obstructive pulmonary disease (COPD) may be at greater risk of developing acute bronchitis.
  • Home supportive care includes keeping your fever, low and drinking lots of fluids to prevent dehydration.
  • Wheezing is often treated with inhaled albuterol, either by puffer (HFA) or nebulizer. Steroid medication may be used short-term to help decrease the inflammation within the bronchial tubes.
  • Antibiotics are not commonly prescribed for acute bronchitis but may be prescribed if specifically indicated.

What Are the Signs and Symptoms of Acute Bronchitis?

Inflammation of the bronchial tubes narrows the inside opening of the bronchial tubes. Narrowing of the bronchial tubes results in increased resistance, this increase makes it more difficult for air to move to and from the lungs. This can cause:

  • Wheezing
  • Coughing
  • Chest pain
  • Shortness of breath

The cough may consist of sputum due to the secretions from the inflamed cells that line the bronchi. By coughing, the body attempts to expel secretions that clog the bronchial tubes. If these secretions contain certain inflammatory cells, discoloration of the mucus may result often in a green or yellow color. Sometimes the severity of the inflammation may result in some bleeding.

As with any other infection, there may be associated fever, chills, aches, soreness, and the general sensation of feeling poorly or malaise.

What Causes Acute Bronchitis?

Acute bronchitis occurs most often due to a viral infection, bacteria, or chemical irritants:

  • Viral infections can cause the inner lining of the bronchial tubes to become inflamed and undergo the changes that occur with any inflammation in the body. Common viruses include the rhinovirus, respiratory syncytial virus (RSV), and the influenza virus (flu).
  • Bacteria can also cause bronchitis (a few examples include, Mycoplasma, Pneumococcus, Klebsiella, Haemophilus).
  • Chemical irritants (for example, tobacco smoke, gastric reflux, or solvents) can cause acute bronchitis.

Do Colds Cause Acute Bronchitis?

Anatomically, the larynx divides the upper and lower airways. Colds tend to affect the mouth, throat, and nasal passages while bronchitis describes specific inflammation of the bronchial tubes. The two illnesses can exist at the same time and may be caused by the same virus infection. A cold does not necessarily lead to bronchitis.

What Are the Risk Factors for Bronchitis?

Bronchitis describes inflammation of the bronchial tubes. Smoking is a key risk factor for developing acute bronchitis. Any other illnesses that predispose to similar inflammation also increase that risk (for example, asthma patients and patients allergic to airborne chemicals).

What Procedures and Tests Diagnose Acute Bronchitis?

Acute bronchitis is usually diagnosed through patient history and physical examination.

Patient History

The healthcare professional may ask the following questions about the patient's symptoms:

  • What symptoms exist?
  • When did they start?
  • Is there a related fever?
  • Is sputum being brought up by coughing?
  • Is the sputum color-tinted?
  • Is there any blood tinge?
  • Does the person smoke?
  • Is there a history of asthma or COPD?
  • Does the patient take any medications or inhalers that are used to treat underlying illnesses?
  • What has the patient done to treat the symptoms?
  • Were these measures successful?

Physical Examination

The healthcare professional may examine of the patient's upper airways to look for signs of ear, nose, or throat infection including redness of the tympanic membranes (ear drums), runny nose, and post-nasal drip. Redness of the throat or swelling and pus on the tonsils can help distinguish common cold, tonsillitis, and acute bronchitis symptoms. The neck may be palpated or felt to check for swollen lymph nodes. Listening to the lungs may reveal decreased air entry.

A chest X-ray may be considered by the health care professional if there is a concern that pneumonia or infection of lung tissue is present.

Blood tests are usually not helpful; occasionally, cultures of sputum are done if a bacterial pathogen is suspected.

What Home Remedies Relieve and Cure Acute Bronchitis Symptoms?

Home remedies that soothe acute bronchitis symptoms are relief of symptoms (supportive care). Some people with acute bronchitis only need to drink plenty of fluids to maintain proper hydration, and humidified air to cure bronchitis.

What Medications and Other Therapies Treat Acute Bronchitis?

Decreasing inflammation is the goal of treating acute bronchitis:

  • Albuterol inhalation, either with a handheld device (meter-dosed inhaler, MDI) or nebulizer will help dilate the bronchial tubes.
  • Short-term steroid therapy will help minimize inflammation within the bronchial tubes.
  • Prednisone is a common prescription medication that enhances the anti-inflammatory effects of the steroids produced within the body by the adrenal glands.
  • Topical inhaled steroids may also be of benefit with fewer potential side effects.
  • Acetaminophen (Tylenol and others), nonsteroidal anti-inflammatory (NSAIDs) like ibuprofen (Advil, Motrin), naproxen (Aleve, Anaprox, Naproxen), and aspirin can treat fever and decrease the inflammatory response.

People with medical conditions such as high blood pressure should be careful to choose those products approved for people with high blood pressure because some cough/cold formulations may increase a person's blood pressure to elevated or dangerous levels. People with diabetes should choose cough and cold products that will not affect their blood glucose levels. If you are unsure which products are safe, contact your doctor or pharmacist for advice.

For people with underlying lung diseases like asthma or COPD (emphysema and chronic bronchitis), increased use of albuterol or similar inhaled medications may be indicated. However, contact your doctor if you are considering altering your medications.

Although keeping hydrated helps remove secretions into the bronchi, other treatments (for example, Mucinex, Robitussin, and others that contain guaifenesin) can sometimes help clear secretions.

Cough is a very violent action that results in the dynamic collapse of the airways. This collapse results in the walls of the airways banging against one another. This action of cough can cause further inflammation and help perpetuate the problem by sustaining and increasing inflammation. Cough suppression with cough drops or other liquid suppressants (for example, Vicks 44, Halls, and cough syrups that contain dextromethorphan) help to break this vicious cycle. In addition, if the person smokes, they should stop. If acute bronchitis is caused by inhaled smoke or chemicals, the patient should be removed from these irritant sources.

How Long Does It Take for Bronchitis to Go Away?

Acute bronchitis usually resolves spontaneously (about 2-3 weeks) with supportive care. If wheezing and shortness of breath occur, seek medical care. For people who have underlying lung conditions, the inflammation can cause lung tissue to function improperly. Pneumonia or infection of the lung tissue itself may develop.

Man with chest pain

Is Bronchitis Contagious?

Chronic bronchitis describes a group of symptoms (including airway inflammation, over-production of phlegm, and cough), which can have various causes and are the result of repeated injury or irritation to the lungs.

  • Chronic bronchitis is not contagious if the cause is due to smoking, air pollution, or other inhaled irritants.
  • Chronic bronchitis is contagious if the cause is viral or bacterial infection.
Reviewed on 11/14/2022
References
Fayyaz, J., et al. "Bronchitis, Acute and Chronic." Medscape. May 19, 2018.

Fauci, A.S., et al. Harrison's Principles of Internal Medicine, 20th Ed. United States: McGraw-Hill Education, 2018.