This will be accomplished by performing a randomized, double blind, placebo-controlled, parallel group study that will compare a widely used and well-tolerated non-steroidal anti-inflammatory drug, ibuprofen 600 mg three times daily, with placebo. PGE will be measured directly in the lower respiratory tract by sampling the lung with the technique of bronchoalveolar lavage. Secondary measures will be made, quantifying PGE in induced sputum and quantifying PGE metabolites in blood and urine. In addition, the current proposal will determine if biochemical measures of lung repair are restored by treatments that block PGE production. Additional outcomes will also be assessed including the effect of treatment on PGD and other eicosanoids and assessing IL-8 and neutrophils in sputum and BAL fluid and selected inflammatory biomarkers present in serum that may be associated with lung function decline. Finally, in an accompanying Ancillary Study, the current proposal will determine if alveolar macrophages over-produce PGE and/or PGD in COPD and will determine if the microRNA miR-146a modulates the production of these prostaglandins, as we have demonstrated for lung fibroblasts. The Ancillary Study will also determine if genetic variation in a miR-146a is related to differential expression.