From the Guidelines
The most appropriate medication for this patient would be metformin, which works by inhibiting gluconeogenesis (answer C). This 36-year-old woman presents with classic signs of polycystic ovary syndrome (PCOS), including irregular menstrual cycles, infertility, obesity, hirsutism, and acne. Her elevated hemoglobin A1c of 7.5% indicates diabetes or prediabetes, which commonly accompanies PCOS due to insulin resistance 1.
Mechanism of Action and Benefits
Metformin improves insulin sensitivity by decreasing hepatic glucose production through inhibition of gluconeogenesis and also reduces intestinal glucose absorption and increases peripheral glucose uptake. In PCOS patients, metformin helps restore ovulation, improves menstrual regularity, reduces androgen levels (which cause hirsutism and acne), and may improve fertility outcomes. Additionally, by addressing the underlying insulin resistance, metformin can help with weight management and reduce the risk of developing type 2 diabetes and cardiovascular complications associated with PCOS 1.
Dosage and Administration
The typical starting dose is 500 mg once daily, gradually increasing to 1500-2000 mg daily in divided doses to minimize gastrointestinal side effects. It's essential to monitor the patient's response to metformin and adjust the dosage as needed to achieve optimal glycemic control and minimize side effects.
Lifestyle Modifications
In addition to metformin, lifestyle modifications such as a healthy diet and regular exercise are crucial in managing PCOS. A systematic review and meta-analysis found that lifestyle interventions, including diet and exercise, can improve insulin sensitivity, reduce androgen levels, and promote weight loss in women with PCOS 1.
Conclusion Not Applicable - Direct Answer Only
Metformin is the most appropriate medication for this patient, given its ability to address insulin resistance, improve glycemic control, and reduce the risk of cardiovascular complications associated with PCOS, as supported by recent studies 1.
From the FDA Drug Label
Metformin is an antihyperglycemic agent which improves glucose tolerance in patients with type 2 diabetes mellitus, lowering both basal and postprandial plasma glucose. Metformin decreases hepatic glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity by increasing peripheral glucose uptake and utilization
The most appropriate medication for this patient is metformin, and its mechanism of action is decreasing hepatic glucose production, decreasing intestinal absorption of glucose, and improving insulin sensitivity. The correct answer is inhibiting gluconeogenesis is not explicitly mentioned, but decreasing hepatic glucose production can be related to it. However, the best match among the options is D. mimicking the natural occurrence of insulin is not correct, but improving insulin sensitivity is mentioned. The best choice is C. inhibiting gluconeogenesis is the closest to decreasing hepatic glucose production 2.
From the Research
Mechanism of Action of Metformin
The patient's symptoms, such as irregular menstruation, heavy bleeding, cystic acne, hirsutism, and infertility, are consistent with polycystic ovary syndrome (PCOS) 3, 4, 5, 6, 7. The most appropriate medication for this patient is metformin, which is an insulin sensitizer.
Effects of Metformin on PCOS
Metformin has been shown to:
- Decrease serum lipids, androgen, and insulin levels 3
- Induce ovulation and regular menstrual cycles 3
- Increase pregnancy rates 3, 4
- Improve hyperandrogenism by decreasing androgen levels 4, 6
- Reduce body mass index (BMI) and improve insulin resistance 5, 6
Mechanism of Action
The mechanism of action of metformin is to:
- Increase insulin sensitivity, thereby reducing insulin resistance 5, 6
- Decrease glucose production in the liver by inhibiting gluconeogenesis 3
- The correct answer is:
- C. inhibiting gluconeogenesis However, other options are also related to the effects of metformin, such as:
- B. increasing leptin sensitivity (indirectly, by improving insulin sensitivity)
- D. mimicking the natural occurrence of insulin (not directly, but by increasing insulin sensitivity)
Note: The other options are not directly related to the primary mechanism of action of metformin. Option A (activating glucagon-like peptide-1 receptors) is related to other medications, and option E (thickening cervical mucus) is related to contraceptive methods.