Encyclopedia Home / H / Hypersensitivity pneumonitis

Hypersensitivity pneumonitis

  • Alternative Names

    Extrinsic allergic alveolitis; Farmer's lung; Mushroom picker's disease; Humidifier or air-conditioner lung; Bird breeder's or bird fancier's lung


    First, the foreign substance must be identified. Treatment involves avoiding this substance in the future. Some people may need to change jobs if they cannot avoid the substance at work.

    If you have a chronic form of this disease, your doctor may recommend that you take glucocorticoids (powerful anti-inflammatory medicines). Sometimes treatments used for asthma can help people with hypersensitivity pneumonitis.

    Support Groups

    Expectations (prognosis)

    Most symptoms go away when you avoid or limit your exposure to the material that caused the problem.


    The chronic form of this disease may lead to pulmonary fibrosis (a scarring of the lung tissue that often is not reversible).

    Calling your health care provider

    Call your health care provider if you develop symptoms of hypersensitivity pneumonitis.