Improved efficacy of low-dose spironolactone and metformin combination than either drug alone in the management of women with polycystic ovary syndrome (PCOS): a six-month, open-label randomized study

J Clin Endocrinol Metab. 2013 Sep;98(9):3599-607. doi: 10.1210/jc.2013-1040. Epub 2013 Jul 11.


Context: To improve the treatment outcomes in women with polycystic ovary syndrome (PCOS), various drugs like glitazones, oral contraceptive pills, or antiandrogens have been combined with metformin.

Objective: The aim of the study was to compare the efficacy of the combination of low-dose spironolactone and metformin with either drug alone in the management of women with PCOS.

Design and setting: The present study was an open-label, randomized study conducted at a tertiary care referral center.

Patients and intervention: Of 204 women who met the 2006 Androgen Excess-PCOS criteria for PCOS, 198 were randomized into 3 equal groups to receive metformin (1000 mg/d), low-dose spironolactone (50 mg/d), or a combination of both drugs for a period of 6 months. A total of 169 subjects (n = 56 metformin, 51 spironolactone, 62 combination) completed the study.

Main outcome measures: Menstrual cycle pattern, Ferriman-Gallwey score, body mass index (BMI), waist-hip ratio, blood pressure, LH, FSH, total T, glucose and insulin sensitivity indices were measured at baseline (0 mo) and 3 and 6 months after the intervention. Recording of adverse events and drug compliance was assessed at each of the visits.

Results: The 3 groups had comparable mean age and BMI at baseline. By 6 months, menstrual cycles/y increased, whereas Ferriman-Gallwey score, serum total T, and area under the curve-glucose and -insulin decreased significantly (P < .05) in the combination group as compared to either drug alone. There was no significant change in body weight, BMI, waist-hip ratio, and blood pressure in any of the 3 groups. The combination group had better compliance than either drug alone, and the adverse event rate was not higher.

Conclusion: The combination of low-dose spironolactone with metformin seems superior to either drug alone in terms of clinical benefits and compliance in women with PCOS.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Blood Glucose
  • Blood Pressure / drug effects
  • Body Composition / drug effects
  • Body Mass Index
  • Drug Therapy, Combination
  • Female
  • Follicle Stimulating Hormone / blood
  • Humans
  • Hypoglycemic Agents / administration & dosage
  • Hypoglycemic Agents / therapeutic use*
  • Insulin / blood
  • Insulin Resistance
  • Luteinizing Hormone / blood
  • Menstrual Cycle / drug effects
  • Metformin / administration & dosage
  • Metformin / therapeutic use*
  • Mineralocorticoid Receptor Antagonists / administration & dosage
  • Mineralocorticoid Receptor Antagonists / therapeutic use*
  • Polycystic Ovary Syndrome / blood
  • Polycystic Ovary Syndrome / drug therapy*
  • Polycystic Ovary Syndrome / physiopathology
  • Spironolactone / administration & dosage
  • Spironolactone / therapeutic use*
  • Testosterone / blood
  • Treatment Outcome
  • Waist-Hip Ratio


  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin
  • Mineralocorticoid Receptor Antagonists
  • Spironolactone
  • Testosterone
  • Luteinizing Hormone
  • Follicle Stimulating Hormone
  • Metformin