NAC and Metformin have Similar Efficacy in the Treatment of Polycystic Ovarian Syndrome

Polycystic ovary syndrome (PCOS) is a condition in which there is an imbalance of a woman’s female sex hormones that may cause changes in the menstrual cycle, skin changes, small cysts in the ovaries, trouble getting pregnant, and other problems. Current studies clearly link PCOS and insulin resistance. A report released in the British Journal of Obstetrics and Gynecology in 2000 indicated that up to 40% of women with PCOS have either impaired glucose tolerance or Type 2 Diabetes by age 40. Symptoms of PCOS can vary significantly. Changes in the menstrual cycle can include: absent periods, usually with a history of having one or more normal menstrual periods during puberty; and irregular menstrual periods, which may be more or less frequent, and may range from very light to very heavy. PCOS may also lead to the development of male sex characteristics (virilization), including: decreased breast size; deepening of the voice; enlargement of the clitoris; increased body hair on the chest, abdomen, and face, as well as around the nipples (called hirsutism); and thinning of the hair on the head, called male-pattern baldness. Other skin changes can include: acne that gets worse; and dark or thick skin markings and creases around the armpits, groin, neck, and breasts due to insulin insensitivity.

N-acetyl cysteine (NAC) is an altered form of the amino acid cysteine, which is commonly found in food and synthesized by the body. NAC has been reported to have numerous health benefits and has been used in the treatment of mental health problems, infections, heart disease, insulin resistance, detoxification and liver dysfunction, and as a general antioxidant. Metformin, on the other hand, is an oral anti-diabetic drug that is a firstline treatment for diabetes, especially in individuals who are overweight/obese and have normal kidney function. Metformin affects the way insulin controls blood glucose and lowers testosterone production. It slows the growth of abnormal hair and, after a few months of use, may help ovulation to return.

A recent study, published in the European journal of obstetrics, gynecology, and reproductive biology was conducted to evaluate the clinical, endocrine and metabolic effects of metformin and NAC in patients with PCOS. In this prospective trial, 100 women with PCOS were randomly divided to receive metformin (500 mg three times daily) or NAC (600 mg three times daily) for 24 weeks. Androgen levels (ie. “male hormone” levels), lipid profiles, hirsutism scores (excessive hairiness in women), menstrual irregularity, insulin sensitivity and tumour necrosis factor-α (TNF-α) levels were measured at baseline and after the treatment period. Both treatments resulted in a significant decrease in body mass index (BMI; an indication of weight status), hirsutism score, fasting insulin, free testosterone and menstrual irregularity compared with baseline values, and both treatments had equal efficacy. NAC led to a significant decrease in both total cholesterol and LDL cholesterol (ie. the “bad” cholesterol), whereas metformin only led to a decrease in total cholesterol level. The authors concluded that Metformin and NAC appear to have comparable effects on high testosterone, high insulin, and menstrual irregularity in women with PCOS, representing a potentially novel treatment for this (Eur J Obstet Gynecol Reprod Biol. 2011 Aug 8, PMID: 21831508).