Flu Complications

Overview

Although most cases of influenza (flu) get better without causing other problems, complications sometimes develop.

Possible problems from the flu include:

  • Pneumonia, which is an infection of the lungs. It rarely causes death in young, healthy people. But it can often be life-threatening in older adults, people who have other diseases, and pregnant women.
  • Bronchiolitis. This is an inflammation of the small air passages. It affects infants and is the leading cause of serious lower respiratory illness.
  • Sinusitis. This means the mucous membranes that line the inside of the nose and facial sinuses become infected and inflamed.
  • Croup. Croup is a swelling or blockage in the windpipe. It causes hoarseness, a barking cough, a high-pitched sound when breathing in, and trouble breathing.
  • Chronic obstructive pulmonary disease (COPD) symptoms may get worse.
  • Inflammation of the heart muscle, the sac around the heart, or other muscles.

Related Information

Credits

Current as of: February 9, 2022

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Christine Hahn MD - Epidemiology

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