N-acetyl cysteine (NAC) is an antioxidant supplement that helps the body make glutathione.
Why it matters for PCOS
NAC is a derivative of the amino acid cysteine. In the body it supports production of glutathione, the main antioxidant that helps reduce oxidative stress. In PCOS it has been studied for oxidative stress and fertility-related outcomes, and some trials have also looked at acne and insulin levels.
NAC is sold as a supplement, not a prescription medicine. The PCOS evidence is still limited and partly from small studies, so it is not a replacement for medical care. Check with a doctor or pharmacist before starting, especially if you take other medicines, have asthma, or are pregnant.
This glossary is education, not diagnosis. For your own situation, ask a doctor or pharmacist.