Acetylcysteine, a mucolytic agent, has a strong mucolytic effect, reducing the viscosity of sputum and making it easy to cough up. Also, the drug has an important role in maintaining proper glutathione levels. It protects cells from cytotoxic damage caused by low levels of glutathione in the body. The drug can be used in the treatment of the following diseases: 1. It is used in the treatment of chronic respiratory disease infections that secrete large amounts of thick sputum, including acute exacerbations of chronic obstructive pulmonary disease, acute attacks of chronic bronchitis, emphysema, and bronchiectasis. 2. It can be used to try to treat interstitial lung fibrosis.