Pneumonia - Signs, Symptoms, and Complications - Signs, Symptoms, and Complications

The signs and symptoms of pneumonia can be mild or serious. Young children, older adults, and people who have serious health conditions are at risk for developing more serious pneumonia or life-threatening complications.

Signs and symptoms

The signs and symptoms of pneumonia may include:

  • Chest pain when you breathe or cough
  • Chills
  • Cough with or without mucus
  • Fever
  • Low oxygen levels in your blood, measured with a pulse oximeter
  • Shortness of breath

You may also have other symptoms, including a headache, muscle pain, fatigue (extreme tiredness), nausea (feeling sick to your stomach), vomiting, and diarrhea.

Older adults and people who have serious illnesses or weakened immune systems may not have typical symptoms. They may have a lower than normal temperature instead of a fever. Older adults who have pneumonia may feel weak or suddenly confused.

Sometimes babies don’t have typical symptoms either. They may vomit, have a fever, cough, or appear restless or tired and without energy. Babies may also show the following signs of breathing problems: 

  • Bluish tone to the skin and lips
  • Grunting
  • Pulling inward of the muscles between the ribs when breathing
  • Rapid breathing
  • Widening of the nostrils with each breath


Often, people who have pneumonia can be successfully treated and do not have complications. Complications from pneumonia are more common in children, older adults, and people with other serious diseases.

This video describes complications that can happen from pneumonia. Read below for a more complete list of possible complications. Medical Animation Copyright © 2020 Nucleus Medical Media Inc. All rights reserved.

Complications of pneumonia that may be life-threatening include:

  • Acute respiratory distress (ARDS) and respiratory failure, which are common complications of serious pneumonia.
  • Kidney, liver, and heart damage, which happens when these organs don’t get enough oxygen to work properly or when your immune system responds negatively to the infection.
  • Necrotizing pneumonia, a condition that develops when your infection causes your lung tissue to die and form lung abscesses (pockets of tissue filled with pus). It also makes your pneumonia harder to treat. You may need surgery or drainage with a needle to remove the pus.
  • Pleural disorders. The tissues that cover the outside of your lungs may become inflamed, and the chest cavity around your lungs may fill with fluid and pus.
  • sepsis , which happens when bacteria from your lungs gets into your blood and causes inflammation throughout your body.