The most common type of lung fibrosis—scarring of the lungs—is idiopathic, meaning of unknown cause. Researchers are urgently trying to find ways to prevent or slow idiopathic pulmonary fibrosis (IPF) and related lung conditions, which can cause worsening shortness of breath, dry cough, and extreme fatigue. Average survival following diagnosis of IPF is just three to five years, and the disease has no cure.