1. Acute exacerbations (AEx) in idiopathic pulmonary fibrosis (IPF) patients occur in 5-10% of patients annually and are associated with high mortality. 2. The pathophysiology of AEx-IPF involves diffuse alveolar damage superimposed on the underlying usual interstitial pneumonia pattern. Several hypotheses exist for the triggers but occult infection is not commonly supported. 3. Risk factors for AEx-IPF include lower lung function and more severe fibrosis on imaging. Invasive procedures can precipitate events. Treatment of gastroesophageal reflux may reduce risk.