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Why Does Metformin Make You Poop?

Metformin is a first-line prescribed medication for treating type-2 diabetes, particularly in obese or overweight people. In the treatment of polycystic ovary syndrome, Metformin used. Metformin was discovered in 1922. French physician Jean Sterne began a study in humans in the 1950s. As a medication, it was introduced in 1955.

It is now on the World Health Organization’s List of Essential Medicines. Metformin is generally well tolerated. But it also has some adverse effects like Diarrhea, nausea, and abdominal pain. It has less risk of causing low blood sugar.

Why does Metformin Cause Diarrhea?

People who take Metformin, Diarrhea is the biggest concern as it affects roughly half of the people. Nausea, vomiting, and Diarrhea are the most common side effects. These tummy troubles are the most common reason why people stop taking the medication. Metformin causes gastrointestinal intolerance. The mechanism is pretty much unclear. However, there are different hypotheses proposed.

It is found that Metformin structure has some similarities with 5-hydroxytryptamine, 5-HT3 receptor-selective agonists, and is transported Serotonin Reuptake Transporter (SERT). The release of serotonin (5-hydroxytryptamine) from the intestinal results in Diarrhea, nausea, and vomiting, which has a similar link with Metformin intolerance.

Duodenal biopsy study on Metformin naïve individuals found that Metformin stimulates the release of serotonin from enterochromaffin cells. This effect is not through the 5-HT3 receptor. The receptor inhibits when the response is not altered.

There are different other Hypothesizes regarding Diarrhea caused by Metformin.

Metformin Side-Effects

If you ask a room full of people taking Metformin that what their least preferred aspect of this drug is, they’d all likely say, “Running to the bathroom constantly for the first few weeks!”

The biggest problem of Metformin is how it affects the stomach. Metformin can cause various digestive issues almost instantly:

  • Diarrhea
  • Gas
  • Nausea
  • Vomiting
  • General discomfort in your stomach

There are also some rare side effects. They are:

  • Heartburn
  • Rhinitis
  • Low blood sugar
  • Itching or hives
  • Discoloration of the nails
  • Hoarseness

Diabetic Diarrhea:

Diabetic diarrhea is an exasperating gastrointestinal complication of diabetes. It may persist for several weeks to months. It usually accompanies fecal incontinence. The connection between diabetes and diarrhea isn’t clear, but research suggests that autonomic neuropathy may be a factor.

Neuropathy refers to the nerve damages resulting from numbness or pain. If someone has diabetes, high blood sugar levels can damage his/her nerve fibers. It occurs mostly in hands and feet.

Autonomic neuropathy is the damage of nerves that help control the body’s involuntary functions, including the movements of the large intestine. If the large intestine is affected by nerve damage, there might be an experience of alternating periods of constipation and diarrhea.

Another cause which is possible is sorbitol. In diabetic food, people sometimes use sweetener. Sorbitol also is known as sugar alcohol found in diabetic foods as a sweetener. Sugar alcohols usually have lower sugar content and affect blood glucose levels less than table sugar.

On the contrary, they may have a laxative effect, causing stomach cramps and diarrhea.

Metformin Diarrhea Management

For managing the adverse effect of Metformin, there are three tips:

Take Metformin with a meal:

There is less possibility of experiencing problems if your stomach is full. If the doctor prescribed you to take Metformin once a day, it is better to take it with the day’s biggest meal. If the doctor prescribed to take it twice a day, try to take it at opposite ends (i.e., take it with breakfast and lunch).

Switch to extended-release (ER) Metformin:

People, who have prescribed Metformin for the first time usually tend to buy the immediate release (IR) version due to its lower cost. The rate of experiencing stomach problems from it is more. The ER tablets have a coating that slowly releases the medication, causing it to be less upsetting to the stomach.

Careful with dietary changes and supplements:

Changing your diet or taking probiotics may cause stomach upset. But there is no evidence. It is better to make changes in diet under the recommendation of a doctor or dietician.

Can you take Imodium with Metformin?

Imodium is an antidiarrheal drug. Imodium is used to treat conditions like diarrhea (both acute and chronic), traveler’s diarrhea. The total number of medications known to interact with Imodium is 312.

On the other hand, Metformin is in the drug class non-sulfonylureas. Metformin treats conditions like type-2 diabetes, female infertility, Insulin Resistance Syndrome, Polycystic Ovary Syndrome. The total number of drugs known to interact with Metformin is 338.

But no such interactions were found between Imodium and Metformin. It is better to consult the healthcare provider.

Diabetes Constipation Remedy:

Either directly or indirectly, diabetes causes constipation. Diabetes can lead to constant high blood sugar levels, which may cause nerve damage leading to constipation. In some cases, a person’s diet or medication may also cause constipation. The symptoms of constipation are quite uncomfortable, but there are steps to relieve them.

A diabetic patient may not need to see a doctor about constipation. They can try to treat their constipation at home in the following ways:

  • Drinking more water
  • Eating more fiber
  • Doing more exercise

Usually, these steps may naturally encourage bowel movements and help pass stool. Diabetic people need to manage their blood sugar levels to less likely to develop constipation and reduce the risk of having other symptoms and complications, including nerve damage.

Diabetic Enteropathy:

The damage to the nerves generated by diabetes in the intestines causes the food you eat to slow down or stop there as the body processes it. Such an act leads to constipation and helps to create breeding for unhealthy bacteria.

As a result, you may be facing problems like a combination of constipation and diarrhea, which is the most common symptom of enteropathy.

On the other hand, it may be hard to control bowel movements, and sometimes stool might leak from the rectum. The problem gets worse after a meal.

Is Metformin Bad For You?

Metformin can cause more severe side effects, but these are rare. Lactic acidosis is the most serious of them. It is a condition caused by a buildup of lactic acid in the blood. This condition can only occur if too much accumulation of Metformin in the blood due to chronic or acute kidney problems.

Metformin Diarrhea Prevention:

  • It is better to take Metformin with meals to reduce gastrointestinal side effects if you want to take it at a time when you don’t precisely eat, snack on some proteins before taking Metformin.
  • Chewing gums has the capability of relieving various gastrointestinal side effects like nausea and stomach pain.
  • Suppose you take Metformin in an empty stomach and feel nauseous try to eat a little bit. Even if you don’t feel like eating when experiencing nausea, you will feel a lot better if you eat.
  • The extended-release (ER) version of Metformin causes far fewer gastrointestinal problems than regular immediate-release (IR) version. So switch to the ER version of Metformin.
  • Lower the dose of Metformin temporarily if the side effects feel quite severe and increase it slowly.
  • Take vitamin B12 supplements if you are experiencing vitamin B12 deficiencies.
  • Try out several different brands with various manufacturers, testing out the immediate and extended-release so you can find out which medication works best for you, and you experience the least amount of side effects.

Does Metformin Cause Constipation?

Many people complain of facing side effects like nausea, stomach upset, and diarrhea when they start taking the medication. Some other reports show that people complain of having constipation as a side effect to this drug, but only a few. So Metformin may cause constipation, but it is a rare case.

What does Metformin do to you?  

Metformin working mechanism is mainly three:

  • Decrease sugar production by the liver- the liver can metabolize sugars from other substances and release it. But Metformin inhibits the release of an enzyme, which helps in sugar production, resulting in less sugar release in the blood.
  • Increase in the amount of sugar utilization in the muscles and the liver- it is known that a significant “sink” for excess sugar is muscles. Metformin can reduce the amount of sugar into the blood by driving sugar into the muscles.
  • Preventing the breakdown of fats (lipolysis) reduces the number of fatty acids available; thus, the production of sugar is less.

What Does Metformin Do For Diabetes?

Metformin is a drug that is used to treat Type-2 diabetes. It increases the ability of cells to uptake more glucose by boosting their sensitivity to insulin. It decreases the amount of glucose made by the liver and reduces the absorption of glucose from the intestine.

Metformin works in a great way to control diabetes. The method of measuring how effective it is though HbA1C. HbA1C is a blood test that shows an average of the blood sugar level amazingly over the past three months.

Metformin miraculously reduces the HbA1C by an average of 1.5%, which is a considerable improvement for diabetic control in the world. Metformin helps improve diabetes control and reduces the incidence of some complications like heart attack, stroke, etc.

Why Metformin Makes You Sick?

People in the age group 18-60 who experience no other medical conditions or take no other medications are most likely to experience side effects like:

  • Diarrhea, nausea, flatulence, indigestion, headache, muscle ache, lack of energy are side effects that are most commonly reported.
  • Metformin can cause lactic acidosis, but it is a rare condition. Lactic acidosis can be fatal to those who have risks of kidney disease, taking medications that may decrease kidney functions, undergoing radiological studies using contrast media, liver disease, or other medical conditions.
  • Rarely results in anemia, as it may impair vitamin B12 absorption.
  • Excessive intake of alcohol should be avoided as it can enhance the risk of lactic acidosis. Because Metformin and alcohol both cause lactic acid to build up in the blood. Too much lactic acid is a life-threatening condition.
  • People who have severe renal impairments should avoid Metformin. People with an estimated glomerular filtration rate (eGFR) of less than 45ml/min should not be initiated to Metformin.
  • People, when they are restricted from food or fluid intake, should discontinue taking Metformin temporarily. If they tend to consume, they are most likely to develop dehydration, low blood pressure, and kidney damage.

Why take Metformin?

Metformin is one of the safest and most effective medications that help control blood sugar levels in type-2 diabetes and prediabetes. It helps to improve blood sugar control by decreasing the HbA1C count.

Metformin also plays a role in preventing cancer formation since diabetic people are a risk of developing certain cancers.

The FAQs About Metformin

Q. Why does Metformin give you Diarrhea?

Answer: It is a side effect of Metformin, which gives you Diarrhea. Metformin induced the secretion of GLP-1, which generally increase insulin secretion. It is also bad at the same time as it increases glucose content in the intestine, which leads to osmotic Diarrhea.

Q. Does Metformin Diarrhea go away?

Answer: After taking Metformin side effects like Diarrhea will stop in a week or two. Metformin Diarrhea is temporary. Once your body is fully adjusted to this medication, there will be no such side effects.

Related Reading:

  1. When to Take Metformin Before or After Meals
  2. What to Know Before You Lose Weight With Metformin

Dr. SM Kamal Hasan, MBBS(Medicine), Rangpur Medical College and Hospital Rangpur- Dinajpur Highway, Cantt, Near Central Jail, Rangpur 5400, Bangladesh