N‑Acetylcysteine (NAC) is a versatile compound widely recognized for its role in supporting respiratory health, liver protection, and overall cellular defense. It acts as a precursor to glutathione, one of the body’s most important antioxidants, helping to neutralize harmful free radicals and maintain oxidative balance. Clinically, NAC is used to manage chronic respiratory conditions such as bronchitis and chronic obstructive pulmonary disease, where it works as a mucolytic agent to thin and loosen thick mucus, making breathing easier. It is also employed in cases of acetaminophen overdose, where its ability to replenish glutathione reserves protects the liver from severe damage. Beyond these established uses, NAC has been explored for its potential in supporting mental health, reducing inflammation, and improving immune function. Its broad therapeutic applications make it a valuable agent in both acute medical emergencies and long‑term health management strategies.