Metformin Side Effects: PCOS Treatment

Is your PCOS being treated with metformin?

Want to know about metformin side effects in PCOS treatment?

In this article you will know all about metformin, PCOS and metformin side effects.

Metformin side effects

What is Metformin?

Metformin is a drug which is prescribed for type 2 diabetes. It is also prescribed “off-label” for the treatment of PCOS (polycystic ovarian syndrome).  Metformin belongs to class of biguanides. It is the only drug left in its family which is being used for the treatment of type 2 diabetes. Metformin is taken in oral forms and can be in a form of tablet or solution. It should be taken only on doctor’s advice.  Metformin is available in the market under the following brand names:

Who should not use Metformin?

Metformin should not be used by kidney patients. People who have severe kidney problems should not use this drug as it can cause serious health concerns. People who are suffering with metabolic acidosis or ketoacidosis should consult their doctor before using metformin.

Functions of Metformin and Dose for PCOS

There are three basic function of metformin:

  • Signals liver to produce less glucose
  • It can lower insulin resistance i.e. your muscle take up or absorb glucose with help of insulin
  • Signals intestine to absorb less glucose from food you eat

In PCOS the required amount to start with is 500mg(milligrams) daily, and the dose is increased gradually to reduce metformin side effects.

What is PCOS?

PCOS or polycystic ovarian syndrome is an endocrinological disorder or simply you can say it is a hormonal disorder in which a woman experiences irregular or no periods. She can even have heavy flow or longer periods too. The amount of androgen “male hormone” increases in her blood and she faces hirsutism i.e. hair on face and body.  Women with PCOS may have insulin resistance and can have gestational diabetes later in their pregnancies. Their risk of miscarriage is also increased. All these problems occur due to lack of female hormone and more androgen levels.

Metformin as PCOS treatment

Metformin is used in PCOS treatment because it lowers the blood sugar level if you have insulin resistance. It also lowers the LDL cholesterol levels and reduces the risk of heart problems. If you are obese then it will help in losing weight and increasing the chance of fertility.  It helps in maintaining normal ovulation. It encourages regular monthly periods and if you are pregnant it lowers the chances of miscarriage. Thus metformin also improve fertility chances.

Metformin Side Effects

Like every medicine metformin also have side effects. Metformin side effects PCOS are as follows:

Serious side effects

If you observe or feel any of the following side effects consult your doctor immediately:

  • Cough or hoarseness
  • Fever or chills
  • Cramping or muscle pain
  • Loss or decreased appetite
  • Rapid breathing
  • Lactic acidosis (serious and life threatening problem in which lactic acid is buildup in blood)
  • Side or lower back pain
  • Difficulty in urination
  • Feeling drowsy or sleepiness
  • Diarrhea
  • Stomach or abdominal pain or discomfort

Common side effects

Besides these side effects there are few not to worry side effects of metformin which include:

  • Metallic taste in mouth
  • Bloating
  • Flatulence
  • Vomiting and nausea
  • Heartburn
  • Feeling you are full
  • Weight loss
  • Stomach pain
  • Constipation

If you are taking metformin with food then it can help in dealing with these side effects. But if you increase the dose then these side effects will appear again.

Rare Side Effects of Metformin

Some rare side effects of metformin include rashes, palpitations, sweating, headache, slurred speech, and difficulty sleeping.

Long Term Side Effects of Metformin

If you have been using metformin for a very long time then you can experience some memory related problems which include memory loss in older age. Parkinson’s disease or Alzheimer disease can occur if prolonged use of metformin is carried out. These medical conditions are related to Vitamin B12 deficiency which is caused by metformin.

Vitamin B12 Deficiency

Long term and high dose use of metformin can cause vitamin B12 deficiency. Low levels of Vitamin B12 results in mood swings and memory loss. It is important to keep a check on your vitamin B12 levels and intake. It is better to take this vitamin more in your diet as it can be easily found in dairy products, chicken, eggs, beef and fortified cereals. If you are a vegetarian then ask your doctor for supplements as they are also a good source of vitamin B12.


National Health Service (U.K.): “Metformin.”

Medlineplus: “druginfo, meds, a696005.”

Drugs: “sfx, metformin side-effects.”

Lashen H. (2010). Role of metformin in the management of polycystic ovary syndrome. Therapeutic advances in endocrinology and metabolism, 1(3), 117–128.

Drugs: “metformin.”

WebMD: “Diabetes, Metformin side effects.”

VeryWellFamily: “Metformin and PCOS.”

Healthline: “Health, Metformin side effects”


4.9/5 - (7 votes)

Follow me!

2 thoughts on “Metformin Side Effects: PCOS Treatment

  1. Marinda says:

    Heya i am for the first time here. I found this board and I find It truly useful & it helped me out a lot. I hope to give something back and aid others like you helped me.

  2. Willie says:

    Admiring the time and energy you put into your website and detailed information you provide. It's awesome to come across a blog every once in a while that isn't the same outdated rehashed information. Great read! I've saved your site and I'm including your RSS feeds to my Google account.

Leave a Reply

Your email address will not be published.