Effects of N-acetylcysteine on semen parameters and oxidative/antioxidant status

Urology. 2009 Jul;74(1):73-6. doi: 10.1016/j.urology.2009.02.034. Epub 2009 May 9.


Objectives: To examine whether a beneficial effect of N-acetylcysteine (NAC) on semen parameters and oxidative/antioxidant status in idiopathic male infertility exists. The production of reactive oxygen species is a normal physiologic event in various organs. However, overproduction of reactive oxygen species can be detrimental to sperm and has been associated with male infertility.

Methods: Our study included 120 patients who had attended our clinic and were diagnosed with idiopathic infertility according to medical history and physical and seminal examination findings, as initial evaluations. The patients were divided randomly into 2 groups. Those in the study group (60 men) were given NAC (600 mg/d orally) for 3 months; the control group (60 men) received a placebo. The oxidative status was determined by measuring the total antioxidant capacity, total peroxide and oxidative stress index in plasma samples. The sperm parameters were evaluated after NAC treatment and were compared with those in the control group.

Results: NAC had significant improving effects on the volume, motility, and viscosity of semen. After NAC treatment, the serum total antioxidant capacity was greater and the total peroxide and oxidative stress index were lower in the NAC-treated group compared with the control group. These beneficial effects resulted from reduced reactive oxygen species in the serum and reduced viscosity of the semen. No significant differences were found in the number or morphology of the sperm between the 2 groups.

Conclusions: We believe that NAC could improve some semen parameters and the oxidative/antioxidant status in patients with male infertility.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Acetylcysteine / therapeutic use*
  • Adult
  • Humans
  • Infertility, Male / drug therapy*
  • Infertility, Male / metabolism*
  • Male
  • Oxidation-Reduction
  • Semen / drug effects*
  • Semen / metabolism*
  • Spermatozoa / drug effects*


  • Acetylcysteine