n-acetylcysteine + pirfenidone

A **combination therapy** of **n-acetylcysteine (NAC)** and **pirfenidone** is used experimentally for treating idiopathic pulmonary fibrosis (IPF). N-acetylcysteine acts as an antioxidant, replenishing intracellular glutathione and reducing oxidative stress, while pirfenidone is an antifibrotic agent that inhibits the synthesis of collagen and downregulates profibrotic and inflammatory mediators. This combination has been tested for potential additive or synergistic benefit in slowing disease progression in IPF patients, but results are mixed, with some studies indicating possible negative effects on lung function decline compared to pirfenidone monotherapy[1][2][3]. There is emerging evidence that the combination may be cost-effective and well-tolerated, though definitive efficacy and safety outcomes require further investigation[4].