Alternative Names

Bronchopneumonia; Community-acquired pneumonia

Definition of Pneumonia

Pneumonia is a respiratory condition in which there is infection of the lung.

Causes, incidence, and risk factors

Pneumonia is a common illness that affects millions of people each year in the United States. Germs called bacteria, viruses, and fungi may cause pneumonia.


The most common symptoms of pneumonia are:

Signs and tests

If you have pneumonia, you may be working hard to breathe, or breathing fast.


Your doctor must first decide whether you need to be in the hospital. If you are treated in the hospital, you will receive fluids and antibiotics in your veins, oxygen therapy, and possibly breathing treatments. It is very important that your antibiotics are started very soon after you are admitted.

Expectations (prognosis)

With treatment, most patients will improve within 2 weeks. Elderly or debilitated patients may need longer treatment.


Allen J. Blaivas, DO, Clinical Assistant Professor of Medicine, UMDNJ-NJMS, Attending Physician in the Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Veteran Affairs, VA New Jersey Health Care System, East Orange, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 4/27/2010

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ADAM Medical Encyclopedia

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