What does pneumonitis mean?
Pneumonitis is a medical term for inflammation of the lungs in which the underlying cause is usually not a conventional respiratory infection. It may result from exposure to chemicals or dust, certain medications, radiation, or an autoimmune reaction. Hypersensitivity pneumonitis, for example, develops when the immune system reacts to repeatedly inhaled organic particles. The term is also used in more specific combinations such as drug-induced, chemical, and acute pneumonitis. Although pneumonitis and pneumonia can produce similar symptoms, including cough, breathlessness, and fatigue, their causes differ: pneumonia is an infection, whereas pneumonitis primarily denotes inflammation. The word is important in medicine, pharmacology, and occupational safety because recognizing a noninfectious cause can lead to removing the trigger and treating the inflammation appropriately.
nounPneumonitis is inflammation of lung tissue, usually caused by a noninfectious factor such as an inhaled chemical, medication, radiation, or autoimmune disease. It differs from pneumonia, which is an infection of the lungs.
- Inflammation of the lung tissue, especially when caused by a noninfectious agent.
"The scan revealed drug-induced pneumonitis, so the medication was discontinued immediately."
"The worker developed chemical pneumonitis after inhaling corrosive fumes."
"Her cough was eventually attributed to a rare form of pneumonitis caused by an immune reaction."
The plural is uncommon because the condition is usually referred to in the singular or without a grammatical number.
"Cases of pneumonitides are more likely to be reported in specialist medical literature than in general usage."
The “-itis” ending means inflammation, not infection: pneumonitis can be triggered by a drug, chemical, or autoimmune response.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does pneumonitis come from?
Pneumonitis combines the combining form pneumo-, from Greek pneumōn meaning “lung,” with the suffix -itis, used in medical terminology for inflammation. The modern word developed through the use of Greek elements within scientific and medical English. Its relatives include pneumonia, pneumonectomy, and pneumoconiosis, all of which refer to the lungs or conditions affecting them.
Related word forms
How pneumonitis is actually used
This is primarily a clinical term, used in medicine and occupational health. It is often discussed without a plural, though the formal plural pneumonitides is recognized.
Easily confused with pneumonitis
Pneumonitis is inflammation of lung tissue, whereas pneumonia specifically refers to an infection of the lungs.