Acetylcysteine Injection is a versatile pharmaceutical agent with two primary mechanisms of action. As a mucolytic, its free sulfhydryl group disrupts the disulfide bonds in mucoproteins, breaking down thick mucus and reducing its viscosity. This action facilitates easier clearance of secretions from the respiratory tract. Additionally, it serves as a potent antioxidant and hepatoprotective agent by restoring depleted glutathione levels, a critical endogenous antioxidant.

The primary indication for Acetylcysteine Injection is as an antidote for acetaminophen (paracetamol) overdose, administered to prevent or lessen hepatic injury in both adults and pediatric patients weighing 5 kg or more. It is also indicated as adjunctive therapy for patients with abnormal or viscid mucous secretions associated with bronchopulmonary diseases, pulmonary complications of surgery, and cystic fibrosis. For intravenous use, it is typically administered in a three-bag or two-bag regimen following a pre-treatment assessment. By combining these two distinct therapeutic actions, acetylcysteine injection offers a unique approach to managing both toxicological emergencies and respiratory conditions characterized by excessive or thick mucus.