Polycystic ovary syndrome (PCOS) is a common condition characterized by failure to ovulate or irregular menstrual periods, a tendency toward excess body hair, acne and/or oily skin, and a tendency to be overweight. PCOS affects approximately one in twenty women of reproductive age. While PCOS is a common problem in the infertile population, the cause of PCOS is still not completely understood. There is new information to suggest that the underlying cause, in many women with PCOS, is insulin resistance. Women with PCOS are not diabetic; rather, their insulin levels are frequently elevated. Lowering the insulin levels acts to decrease elevated levels of androgens (male hormones, such as testosterone) and, in many cases, restores ovulation and normal fertility in PCOS patients.
PCOS treatment includes ovulation induction with Clomid (clomiphene citrate) and/or metformin. Metformin can be added to the fertility drug regimen in PCOS patients who fail to ovulate in response to Clomid. Metformin does not have a F.D.A. indication for its use in PCOS, however, there is substantial research on the application of Metformin in this setting and Metformin is being used at reproductive endocrinology and infertility clinics around the world for PCOS treatment.
Metformin has no effect on insulin production; rather, metformin facilitates insulin’s action by sensitizing cells to insulin, resulting in lower insulin production by the body. Metformin should not be used in women with insulin-dependent diabetes, liver dysfunction, kidney disease, or who are exposed to IVP dye (for X-ray testing of the kidneys).
Metformin should not be used in times of acute physical stress such as severe illness (influenza), surgery or recovery from significant trauma. Dehydration should be avoided while taking Metformin. Metformin should not be used with alcohol and we recommend no alcohol intake while attempting to conceive. However, limiting consumption to one drink per day is sensible. Metformin should be discontinued 2 days in advance of surgery.
Metformin may interact with steroids, diuretics, nicotinic acid, oral contraceptives, and coumadin (warfarin sodium). Patients must let us know if they are taking, or anticipate taking, any of these medications. Metformin appears to be safe in pregnancy but should be discontinued as soon as pregnancy is confirmed.
Metformin’s most common side effects include nausea, vomiting, and diarrhea. Starting metformin slowly, and increasing the dose gradually, will help avoid these symptoms. Metformin side effects ten to dissipate as therapy is continued and the body adjusts to the medication. If metformin causes vomiting, it should be discontinued. If diarrhea or nausea is bothersome, reduce the dose for a week and then attempt to resume the higher previous dose. Metformin may cause a metallic taste in the mouth and decreased appetite. Many women lose weight while taking metformin and this is encouraged as long as the patient’s weight exceeds the optimum. Care must be taken to insure a nutritious diet.
Mediations related to metformin, such as Troglitazone, have caused liver injury and even liver failure in a small number of women. Troglitazone was taken off the market in 2000 for these concerns. Persistent vomiting or pain in the upper abdomen while taking metformin should be brought to your fertility specialist's attention.
Metformin rarely causes lactic acidosis, a dangerous condition occurring in approximately 1 in 33,000 women taking metformin. Lactic acidosis occurs most commonly in patients with impaired kidney or liver function, or who are dehydrated. If a patient becomes dehydrated, such as during a bad case of the flu, or develops any serious medical problem metformin should be discontinued until these conditions have been resolved.
Metformin comes as 500 or 850mg pills and may be taken as three different dosing regimens: (Always take metformin with food. If there are unmanageable side effects at an increased dose, the lower dose should be taken and the increase tried again the next week. If it takes 4 or 5 weeks to reach the correct metformin dose, that is okay. Increase the dose of metformin as slowly or as rapidly as tolerated ) *
- Metformin XR 500 mg tabs (XR= extended release= once-daily dosing, this is the Metformin preparation we usually prescribe)
- Take one tablet with dinner for the first week
- Take two tablets with dinner the second week
- Take three tablets with dinner thereafter
- Metformin 500 mg tabs
- Take one tablet with dinner for the first week
- Take one tablet with breakfast and dinner the second week
- Take one tablet with breakfast, lunch, and dinner thereafter
- Metformin 850 mg tabs
- Take 1/2 tablet with dinner for the first week
- Take 1/2 tablet with breakfast and dinner the second week
- Take one full tablet with breakfast and dinner thereafter
Kidney and liver function blood testing will be performed as a baseline before beginning Metformin therapy. The cost of Metformin is approximately $75.00 per month.
*This dosing information is for our patient's general information. It is not intended to be used as a dosing guide by Web site visitors. Under no circumstance should this dosing and treatment information be applied to a particular patient. Each patient's dosage must be individualized based upon their response and numerous clinical factors.
