Aspiration pneumonia is an infection caused by inhaling something other than air into your lungs. This could be food, liquid, saliva or stomach contents. Many people don’t know they’ve aspirated something. Symptoms include fever, shortness of breath, coughing up blood or pus, chest pain and tiredness. Providers treat it with antibiotics.

Aspiration pneumonia is a bacterial infection in your lungs. It can happen when you aspirate, or inhale, something other than air into your respiratory tract.

This can be food, liquid, saliva, stomach acid, vomit or even a small foreign object.

You’ve probably had something “go down the wrong pipe” — meaning that food or liquid went down your windpipe (toward your lungs) instead of your esophagus (toward your stomach). When this happens, your body reacts and you cough it out. But for some people, they’re unable to get it out, and something ends up in their lungs that doesn’t belong there. This can cause bacteria to grow, causing an infection (pneumonia).

Many people with aspiration pneumonia don’t realize this has happened — called silent aspiration. The infection can develop days or even weeks after aspirating.