10 Common & Dangerous Side Effects Of Metformin for Type 2 Diabetes

Medication for Type 2 Diabetes

10 Common and Dangerous Side Effect Of Metformin in Type 2 Diabetes

The side effects of metformin 500 mg, 850 mg and 1000 mg tablets are not mild when you experience them. Especially if you consider that the effect of metformin is not very effective.

It is therefore good to learn the advantages and disadvantages of this drug.

In this article, you will learn the 10 most common (and sometimes deadly) side effects of metformin so you can decide for yourself whether to take it or not.

You'll also learn in this blog how to go through life without metformin and nasty side effects.


What is Metformin?

Metformin is the first medical step in treating type 2 diabetes. You often start with a dose of 500 mg. It is relatively mild in terms of its effect, so the risk of a low blood sugar (hypo) is quite low.

The medicine works in 6 different ways:

  • Reducing glucose production in the liver
  • Increasing the insulin sensitivity of cells
  • Increasing the glucose consumption of cells
  • Inhibition of glucose resorption
  • Increasing glycogen synthesis in cells
  • Increasing the activity of the glucose transporters in membranes

Purpose of this article

These are all fancy words and sentences that say the same thing:

Metformin lowers your blood sugar levels in various ways. In six ways to be precise. There are even indications that this medicine can prolong your life. But that does come at a price in terms of side effects. In this article you will learn the 10 most important ones.

#1 Nausea is one of the most common side effects of metformin

If you start taking metformin, the chance of developing nausea is quite high.

Fortunately not every person is affected by this.

And if this does affect you, it often passes by after a few days or weeks.

But with some people, the side effects of metformin persist and/or are so serious, causing them to have to stop taking metformin early on.

Although this side effect is not very serious (compared to other medication), it is very annoying

nausea side effects of metformin

This is certainly one of the disadvantages of metformin that you should consider when taking this medicine.

#2 Vomiting

Vomiting goes hand in hand with the nausea. And that is not very strange.

People often vomit when they are nauseous. So vomiting is a consequence of the nausea.

Nothing can be done about this. Of course you can take pills against the nausea...

...but that doesn't solve the problem.

With some people, 'the vomiting side effect due to metformin' is so bad that they even lose weight.

In addition, you can also lose a lot of fluids this way which causes even more thirst for example.

#3 Diarrhea is a common side effect of metformin

This is one of the most unpleasant side effects of metformin that occurs relatively often.

Not only can diarrhea literally be fatal due to the associated dehydration (number 3 cause of death in Africa)...

what are the side effects of metformin

...but it is also very impractical.

Imagine that you have just left your home and 10 minutes later you feel it coming.

Of course you can run to the first toilet you see. But that is not always a possibility.

If you take metformin and you suffer from diarrhea, then know that this may persist. So you'll have to make 'arrangements'.

#4 Loss of appetite

This is a side effect which some health workers would say is an advantage.

Why am I saying this?

Because I have regularly read things like this on medical websites:

"Loss of appetite: this can be an advantage for overweight people"

According to these people poisoning yourself with metformin to lose weight is an "advantage". Personally I see poisoning myself as a big disadvantage.

These people may not know it but... losing weight without metformin is also possible. In fact, losing weight by adjusting your diet, is much better for lowering your high blood sugar levels than metformin ever can be.

And for the record: weight gain is not a side effect of metformin.

Loss of appetite is never a good side effect. Smoking also reduces your appetite. But nobody would say smoking is good. Why they say it about metformin is a mystery to me.

#5 Headache

In addition to various gastrointestinal complaints, metformin can also cause various cognitive side effects such as a headache.

A headache is never fun. And if you get it from a pill that should actually improve you, then that's is even worse.

Some people get headaches from high blood sugar levels.

It is therefore ironic and annoying to get a headache from metformin.

metformin side effect headache

Do you find this article helpful? Click on one of the buttons to share it!

#6 Dizziness

Dizziness is also a side effects of metformin. And it is extra dangerous for the elderly.


Because your bone density is declining. This means that a fall will cause a fracture faster. And if you regularly feel dizzy, then the chances of you falling down are greater.

The combination of dizziness and osteoporosis is therefore extra dangerous.

#7 Fatigue

Fatigue in general is one of those side effects of which it is unclear why you have it.

Type 2 diabetes itself also causes fatigue. That is because your blood sugar level is too high and you are unable to absorb the sugars from the blood.

But metformin itself also causes fatigue.

Fatigue due to diabetes or metformin?

So whether your fatigue is due to high blood sugar level or low blood sugar level, is therefore very difficult to determine for diabetics who do not do blood tests. Do you use metformin and are you often tired? Then it could be because of the metformin.

#8 Taste disorders

This is a very weird one that can completely ruin your diet. You can get a metallic taste in your mouth when you use metformin.

The annoying part is that this taste will constantly be present in your mouth.

Although this is not one of the most dangerous side effects of metformin, it is of course very annoying.

Imagine that you are drinking your favorite drink and you have the feeling that you are drinking a glass of liquid rust. Not really tasty right?

#9 Lactic acidosis is a deadly side effect of metformin

This is a very dangerous side effect that can even have a fatal ending.

If you have poor kidney function and you also use metformin, a lactate buildup can occur in your body.

This literally causes your body to acidify from the inside (which means acidosis) which can ultimately cause a coma. In some extreme cases, a lactic acidosis can be fatal.

It is therefore very important to monitor your kidney function. Especially because type 2 diabetes itself can cause kidney damage.

#10 Vitamin b12 deficiency

Long term use of metformin can cause a vitamin b12 deficiency. This is the case with around 30% of the people.

A vitamin b12 deficiency can cause neuropathy.

Since type 2 diabetes itself can also cause neuropathy, it is not always clear what caused the neuropathy in the first place.

You are probably more likely to develop neuropathy, if you have too little vitamin B12, than due to the clogging of your capillaries from sugars.

So make sure that you regularly have your b12 measured if you take metformin. And make sure you take b12 supplements if you are on the low side.

The Diabetes-free Secret

As you can see there are quite a few side effects of metformin that can be very annoying to experience.

Fortunately, there is a way to completely get rid of ALL of your medication within a few weeks.

Recently it has been discovered that it is possible to reverse type 2 diabetes. Everything you need to do this can be found in your local grocery store.

You can reverse type 2 with one powerful principle. It's something I call the"The Diabetes-Free Secret". I have written a number of pages about this secret that will change your life forever. You will learn:

  • Why you got type 2 diabetes
  • What mechanism you can use to reverse diabetes
  • The best tips to be diabetes-free within a few weeks

Enter your e-mail address below and I will send you the E-book for free.


Ben Kuiper

P.s: which side effects of metformin do you suffer from? What have you done about it? Leave a comment below

About the Author

Ben Kuiper is a pharmacist and an expert in the field of type 2 diabetes.

Send this to a friend