Metformin Side Effects And How To Deal With Them

In this Article:
Metformin Side Effects

Metformin side effects include diabetic neuropathy, brain fog and digestive issues. You can address them through diet, Vitamin B12, CoQ10 and exercise. Let us understand the drug Metformin in detail and study different forms of metformin, its uses and common metformin side effects along with how to deal with them.

Metformin: What Is It Used For?

Metformin is an old warhorse in the pharma battle against diabetes. It has been the mainstay in treatment of Type 2 Diabetes for more than fifty years, often matching or outperforming newer drugs.

In fact, many new combination drugs are often created with metformin as one of the main ingredients. Thanks to its long run in the pharmaceutical world, the side effects of Metformin are also well known.

The Metformin-PCOS connection has been studied extensively, since a majority of health complications associated with PCOS (polycystic ovarian syndrome) are due to hyperinsulinemia (high amounts of insulin in the blood stream). Metformin is known to reduce circulating insulin levels. The use of this drug in women with PCOS has shown highly encouraging results.

Most Prescribed Names in Metformin Category Include:

  • Fortamet
  • Glucophage
  • Glucophage XR
  • Glumetza
  • Riomet Diamin
  • Formin
  • Daomet SR
  • Met-500
  • Bigomet

Metformin Side Effects

Metformin Side Effects infographics

Conventional medicine treats Type 2 Diabetes as a chronic disease that requires lifelong management with medication. Needless to say, the longer a person uses a particular medicine, the more likely it is to create side effects in them. So, most people will face metformin side effects along with its benefits.


Common Metformin Side effects:

  • Fatigue
  • Reduced appetite
  • Stomach or abdominal discomfort
  • Macrocytic anemia (red blood cells get too large)
  • Cough or hoarseness of voice
  • Tingling or numbness in the palms and feet
  • Diarrhea
  • Pain in the lower back or in the flanks (sides)
  • Muscle pain or cramping
  • Hair loss
  • Shallow breathing
  • Painful or difficult urination
  • Blurred vision
  • Weight gain
  • Anxiety

Rare Side Effects Of Metformin

Among the rare symptoms, a more common one is lactic acidosis. It results in indications like fast or shallow breathing, a feeling of general discomfort, muscle pains, decreased appetite, loose stools and stomach discomfort.

Why Do These Metformin Side Effects Occur?

Metformin gives great sugar-control benefits to diabetics. The common metfomin side effects are well known and almost all doctors know how to deal with them. All this is great news. However, there is one aspect of metformin side effects that neither patients nor most doctors know.

Metformin side effects are caused because metformin interferes with the absorption, synthesis, transportation, storage, metabolism and excretion of certain nutrients. This happens due to long term use of the drug metformin.

Dr. Ross Pelton, RPh, CCN has made this amazing connection in his research. If diabetics simply put these vital nutrients back into their body, they can actually prevent (or at least reduce) the side effects of metformin. The additional good news is that just a couple of dietary supplements could cover several side effects. These nutrients often cost a fraction of what drugs cost. Within the recommended doses, they have a few or no side effects.

Symptoms Due To Nutrient Loss Caused By Metformin


Metformin causes depletion of Vitamin B12, Folic Acid and CoQ10, leading to feelings of tiredness, weakness and in some cases, even anemia. If you have been feeling tired all the time and are lacking the energy to do anything, you may be missing Vitamin B12, or Folic Acid (Vitamin B9), or Coenzyme Q10 (CoQ10). These nutrients are needed to ensure that red blood cells of the right size are created in the body and cells are able to produce energy.

Tingling or Numb Hands and Feet (Diabetic Neuropathy)

Arms and feet could tingle or feel numb due to depletion of Vitamin B12, which is critical for nerve insulation. Our nerves are like electric wires and we need Vitamin B12 to keep the protective sheath of the nerves healthy. Metformin interferes with B12 absorption in the body. This leads to nerves becoming extra sensitive, almost like having a short circuit. If nerves get deadened instead, one could feel numbness or that ‘pillow walking’ feeling diabetics often complain about.

Memory and Cognition Issues (Brain Fog)

Vitamin B12 depletion could lead to memory and cognition issues, especially in elderly diabetics. Diabetics who have vitamin B12 depletion could suffer from confusion, memory loss, moodiness, abnormal gait, agitation, dizziness, delusions, dementia and even hallucinations. The risk of symptoms relating to a B12 deficiency increases in elderly diabetics. With age, we produce lesser stomach acid and intrinsic factor, both of which are important for digestion and absorption of Vitamin B12 from regular food sources.

Is there an alternative to popping pills?

Reclaim your health, naturally.

Skin And Hair Issues

Vitamin B9 depletion could cause hair loss while Vitamin B12 loss could cause your skin to bruise easily. If you find that your skin bruises a lot easier than it used to/that you have dermatitis/that your skin is a lot more sensitive, you could be missing vitamin B12. Folic Acid (Vitamin B9) depletion could also lead to hair loss.

Digestive Issues

CoQ10 depletion could cause gum problems, while depletion of Vitamins B9 and B12 could cause diarrhea, nausea and loss of appetite. A loss of appetite, nausea and diarrhea could be caused by, both, B12 and Folic Acid (B9) depletion. Since the digestive tract begins with the mouth, we must mention gingivitis or gum problems here. These can happen when CoQ10, another vital nutrient, is depleted from the body by Metformin (Biguanides).

Muscle Pains, Cramps, Swollen Feet and Cardiac/Heart Issues

Diabetics often complain of unexplained pain in the legs, especially calf muscles. The heart is the most important muscle in the human body and loss of CoQ10 causes a feeling of ‘heaviness’ in the heart.  Metformin causes depletion of CoQ10, which is critical for muscle energy. One of the key vitamin-like compounds that is depleted by Metformin (Biguanides) is called Coenzyme Q10 or CoQ10. It is also called ubiquinone, from the word ubiquitous, meaning everywhere. It is needed for energy production in, literally, every muscle of the human body. Depletion of this vital compound leads to lack of energy and muscle pains. Another impact of the loss of CoQ10 on cardiac health shows itself in stubborn swelling in the legs and feet.

The heart is the most energy-demanding muscle in the human body. So, lack of CoQ10 can lead to –

  • High blood pressure
  • Angina (discomfort in the chest)
  • Cardiac arrhythmia (irregular heartbeat)
  • Cardiomyopathy (labored breathing, swelling of feet, bloated belly)
  • Serious conditions like congestive heart failure, mitral valve prolapse and stroke.

How Do I Get Relief From Metformin Side Effects such as Nausea, Stomach Pain, Diarrhea?

These are the most common side effects of metformin. Doctors handle the nausea, stomach pain, diarrhea etc. caused by Metformin by:

  • Adjusting the dose of metformin – Usually they will start you off with a lower dose than the one prescribed previously and then slowly ramp it up.
  • Asking you to take the medicine with meals, instead of taking it on an empty stomach – This way the medicine works at a time when blood sugar is higher, reducing side effects.
  • Prescribing a slow-release version of metformin – This ensures that your body does not feel the impact of the whole dose in one go.

Nevertheless, you need to get back to your doctor regarding these side effects so that he/she can help you cope on a personal level.

Common Dosage (Metformin 500 mg) & Mechanism of Action

Metformin 500 mg is a popular dose of the medicine. It is able to suppress glucose production in the liver. On average, diabetics are found to produce two to three times more glucose in their liver than non-diabetics. Metformin also makes cells more sensitive to insulin. Experts agree that diabetes starts with insulin resistance. Insulin is the courier that carries glucose from your food into cells. When cells resist, insulin is not able to deliver sugar into muscle and fat cells. Sugar then backs up in the bloodstream instead.

Best Dietary Supplements For Relief From Metformin Side Effects

Best Dietary Supplements For Relief From Metformin Side Effects - Vitamin B, CoQ10 and Folic Acid

  • Vitamin B12: 200-1000 mcg, preferably sublingual administration (taken orally under the tongue)
  • Folic Acid or Vitamin B9: 400-800 mcg
  • CoQ10: 30-200 mcg (Upper limit is often cited at 400 mcg)

Vitamin B12

Vitamin B12 is available in several forms. There’s much controversy surrounding which forms of Vitamin B12 are best absorbed by human beings. Manufacturers of each form claim support in the scientific literature for their form. But, something else seems to matter more.  If you have a clear deficiency (identified with an inexpensive blood test), you need upwards of 1000mcg to quickly shore up your Vitamin B12 levels.

Folic Acid or Vitamin B9

Folic Acid or Vitamin B9 may be had separately or may be combined with Vitamin B12 and other Vitamins in the B family in a single Vitamin B-complex capsule. This is because the remaining members of the Vitamin B family (Vitamins B1 through B7), each, has some benefit to offer diabetics. Here, the majority opinion is in favour of the form of B9 (called folate). It is closer to nature than folic acid, which is chemically synthesized.


Finally, the opinion on form of CoQ10 is divided. Some functional medicine practitioners prefer the Ubiquinol form, while others prefer the Ubiquinone form. Whichever one you pick, the closer your supplements are to natural sources (extracted from them), the better absorption and results you’ll have.

Doses are per day, unless stated otherwise, and are based on studies. Please consult your medical doctor for what supplement and dosage would suit you best.

Reducing Metformin Doses With Diet, Exercise and Stress Management

Controlling blood sugar levels must be given top priority and that is why drugs like metformin are suggested for regular use by doctors. However, research also shows that dietary supplements can help you reduce the burden of prescription drugs and their side effects by supporting better blood sugar control.

Intermittent fasting is also recommended by several M.D.s, like Dr.Jason Fung, who believe that Type 2 diabetes can be reversed. Considering diabetes as a dietary disorder, adopting Low Carbohydrate High Fat or LCHF diet as your core diabetic diet principle is also gaining favor among the same functional doctors.

Stress management, including meditation and performing specific yoga poses, have been shown to improve diabetes control.

So, go ahead and take the next step. Share this information with your medical practitioner and get rid of metformin side effects.

Tags : Metformin

Nachiket Rajadhyaksha

Nachiket Rajadhyaksha

Medical Writer
Nachiket holds a first class degree in Pharmacy and is passionate about writing. He believes that subject experts must simplify medical concepts to make them interesting and accessible to everyone.


  1. Drug-Induced Nutrient Depletion Handbook: Ross Pelton, James B. LaValle, Ernest B. Hawkins, Daniel L.Krinsky , 2nd Edition. Supplement Your Prescription: Hyla Cass, M.D.

Leave a Comment

Medical And General Disclaimer for
This article is intended for informational purposes only. The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. strongly recommends that you consult a medical practitioner for implementing any of the above. Results may vary from person to person.

Drug Side Effects Helper

    Health Supplement Identifier

    Write For Us

    Learn More