Acetylcysteine is a medication primarily used to treat acetaminophen overdose and to help loosen mucus in individuals with respiratory conditions. It works by replenishing levels of glutathione, an important antioxidant in the body, which helps to detoxify harmful substances. In addition to its use in overdose situations, Acetylcysteine is also utilized as a mucolytic agent, making it easier for patients to expel mucus from their lungs. It can be administered orally or through inhalation, depending on the condition being treated.