N-acetyl-cysteine treatment improves insulin sensitivity in women with polycystic ovary syndrome

Fertil Steril. 2002 Jun;77(6):1128-35. doi: 10.1016/s0015-0282(02)03133-3.


Objective: To evaluate the effect of N-acetyl-cysteine (NAC) on insulin secretion and peripheral insulin resistance in subjects with polycystic ovary syndrome (PCOS).

Design: Prospective data analysis.

Setting: Volunteer women in an academic research environment.

Patient(s): Six lean and 31 obese subjects, aged 19-33 years.

Intervention(s): Patients were treated for 5-6 weeks with NAC at a dose of 1.8 g/day orally. A dose of 3 g/day was arbitrarily chosen for massively obese subjects. Six of 31 obese patients with PCOS were treated with placebo and served as controls.

Main outcome measure(s): Before and after the treatment period, the hormonal and lipid blood profile and insulin sensitivity, assessed by an hyperinsulinemic euglycemic clamp, were evaluated and an oral glucose tolerance test (OGTT) was performed.

Result(s): Fasting glucose, fasting insulin, and glucose area under curve (AUC) were unchanged after treatment. Insulin AUC after OGTT was significantly reduced, and the peripheral insulin sensitivity increased after NAC administration, whereas the hepatic insulin extraction was unaffected. The NAC treatment induced a significant fall in T levels and in free androgen index values (P<.05). In analyzing patients according to their insulinemic response to OGTT, normoinsulinemic subjects and placebo-treated patients did not show any modification of the above parameters, whereas a significant improvement was observed in hyperinsulinemic subjects.

Conclusion(s): NAC may be a new treatment for the improvement of insulin circulating levels and insulin sensitivity in hyperinsulinemic patients with polycystic ovary syndrome.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Acetylcysteine / administration & dosage
  • Acetylcysteine / therapeutic use*
  • Adult
  • Androgens / blood
  • Drug Administration Schedule
  • Female
  • Glucose Tolerance Test
  • Humans
  • Hyperinsulinism / blood
  • Insulin / blood
  • Insulin / metabolism
  • Insulin Resistance / physiology*
  • Liver / metabolism
  • Polycystic Ovary Syndrome / drug therapy*
  • Polycystic Ovary Syndrome / physiopathology*
  • Prospective Studies
  • Testosterone / blood


  • Androgens
  • Insulin
  • Testosterone
  • Acetylcysteine