Hypersensitivity pneumonitis (pronounced noo-meh-nie-tis) is a lung condition that can make it hard to breathe.
Hypersensitivity pneumonitis is sort of like having an allergic reaction inside your lungs. You breathe something in that irritates your lungs and causes inflammation and sometimes scarring. The inflammation and scarring in your lungs can make it hard to breathe.
People with hypersensitivity pneumonitis can have a hard time breathing. They also may cough and sometimes wheeze.
If you breathe in a lot of bad stuff, hypersensitivity pneumonitis might make you huff and puff.