The reason behind people who have diabetes is unknown. Sugar primarily builds up in the bloodstream; therefore, insulin is not produced in the pancreas, leading to type 1 and 2 diabetes.

There are 3.9 million people affected with diabetes. They are most likely to develop coronary artery disease, chest pain, heart attack, stroke, and nerve damage.
There are no exact causes. You might feel excessive thirst or urination, fatigue, weight hunger, and blurred vision.

Yes, nowadays, it is widespread to get diabetes. Approximately 90% to 95% of them suffer from type 2 diabetes. It is caused mainly by not being physically active, being overweight or obese.

Metformin is most effective in treating the blood glucose level. More than 120 Million people are consuming this medication worldwide. Let us understand in detail why Metformin causes constipation.

What Is Metformin?

Metformin medication treats type 2 Diabetes Mellitus and gestational diabetes. It helps control your blood sugar level (glucose). It is used as an off-label for weight reduction, Polycystic ovary syndrome, Infertility, and obesity.

Metformin is also available in its brand name, Glucophage. Food and Drug Administration approved Metformin for use in 10-year-old children and adolescents.

How Does Metformin Work?

Metformin is the most prescribed drug for diabetes, and it works by lowering the glucose level released from the liver. It helps to produce the existing insulin to work better, reducing the blood sugar level.

If your body is effective and able to metabolize the glucose, the risk of diabetes and some complications such as stroke, heart disease, neuropathy, and retinopathy will be decreased. Metformin belongs to a class of Biguanides ( antihyperglycemic agents) that suppress hepatic glucose production and help control the blood sugar level.

This oral drug helps control blood sugar levels by increasing the AMP-activated protein kinase (AMPK). This will lead our body to restrict glucose produced by the body through non-carbohydrate substances.

If this process gets restricted, there will generally be no glucose production from the Gluconeogenesis process. This will reduce blood sugar levels in your body. Many researchers also prove that this will increase the insulin sensitivity in your body so that extra glucose in the body will be processed through insulin, which leads to blood sugar being in the normal range.

Taking Metformin for a more extended period will lead to Vitamin B12 deficiency, Which leads to fainting and breathlessness. So, the doctor checks your level. In that case, your doctor may know how to determine your sugar level and how to stop taking it.

Will Metformin cause you constipation?

Constipation is known as infrequent bowel movements that last for weeks. Stools are tough, dry, or lumpy. It is sometimes associated with abdominal symptoms of bloating and distension on the left side.

The person who is consuming Metformin can cause constipation in 1% of patients, and it is the most common symptom of Metformin to cause diarrhea than constipation.

The research states that less than 1 percent of Metformin patients will experience constipation. During your Metformin drug therapy, constipation is due to other causes. Metformin is a cause of constipation if you are experiencing symptoms after taking the medication. If it is developed over months or years, it is better to take an alternative cause of constipation other than Metformin.

Symptoms of Constipation are Nausea and vomiting, bloating, indigestion, abdominal pain, abdominal distension, blood in stools, stool abnormality, fever, unexplained weight loss, and difficulty passing stools.

Related Blog: Does Metformin Cause You Weight Loss

Why Does Metformin Cause constipation?

Constipation is a prevalent thing due to the medication affecting many people. People with diabetes should pay more attention to all the symptoms. Depending on the diabetic state, your dosage will be required. When it comes to constipation, you should understand that damage to the nervous system will lead to constipation due to diabetes.
Some of the reasons are listed below,

Metformin constipation: who is at risk?

Diabetic Neuropathy And Gastroparesis

In general, a person with diabetes will develop diabetic neuropathy and nerve damage. It will affect different parts of your body, including the digestive tract. Hence, diabetes with nerve damage will affect the Vagus nerve, responsible for controlling food through the digestive tract.

Due to this, a person will be in a difficult situation to pass solid waste. Therefore, the person will develop and become constipated. The damage to the Vagus nerve can also cause a condition called Gastroparesis.

Diabetes And Diet-Related Constipation

Diabetic patients may develop constipation due to the diet. People with diabetes must eat a very well-balanced diet. Following an unhealthy diet pattern to prevent blood sugar and maintain a healthy body weight will lead to constipation.

Diabetic medication and constipation:

Some medications for diabetes may cause constipation. You should consult with your doctor. If you suspect that the drug is the reason for your constipation, your doctor will confirm and clear your doubt, and sometimes, they may suggest alternative treatments.

Why do people suffer from constipation?

Nerve Damage

There are 62% to 70% of people with diabetes have nerve damage or diabetic neuropathy. The condition develops at any time, depending on how long you have diabetes. We have discussed that the vagus nerve goes to the stomach and intestine, eventually making it hard to move the food out normally, leading to constipation.

This process will be increased during your nighttime. Misfiring nerves cannot contract the muscles that mix and move the stuff into your intestine. So the process will be slowed down, and your colon will observe the waste, making your poop harder and more challenging to pass.

Constipation which stays longer will affect your health, and it will develop problems like fecal impaction, a hard lump of poop that will block your rectum so nothing can get out.
Fluid in your intestine will allow too many bacteria to grow inside. This leads to bloating, belly pain, and diarrhea.


Metformin is a medication used to treat type 2 diabetes. It will help to lower your blood glucose and insulin sensitivity. The drug will cause nausea and diarrhea if you are taking this at the start or raising the dosage; it will usually go in a few weeks.

Some other drugs for diabetes that lead to diarrhea are Acarbose, Colesevelam, Linagliptin, Miglitol, Saxagliptin, and Sitagliptin.

Other conditions:

Some other causes are eating sugar items like many sweet products, such as Maltitol, Mannitol, and Sorbitol. It leads to diarrhea because it belongs to a compound called sugar alcohol. Your body cannot break them down and absorb them entirely, so they pull water into your intestines.

Persons with Type 1 diabetes are at higher risk of getting celiac disease. These people cannot eat gluten (a natural protein found in grains like wheat) because it damages the small intestine.

How long does Metformin constipation last?

Suffering from constipation due to Metformin depends on various reasons and your dosage consumption. On average, it goes away in time. If you do not feel the changes after some days, contact your doctor for a solution to such a condition.

Precautions of Metformin:

It is always necessary for you to take proper care while consuming Metformin. You need to follow some factors if you are taking the drug. Such as:

Kidney problems

The kidney removes Metformin throughout your body. If your kidney doesn’t work, the drug will raise the risk of lactic acidosis. People suffering from severe kidney problems and older than the age of 80 should not take Metformin.

Heart problem

Metformin is not recommended for people with recent acute heart failure or heart attack.
Your heart might not send enough blood to your kidney; this will prevent your kidney from removing the Metformin in your body, resulting in a Higher level of lactic acidosis.

Alcohol Use

While taking Metformin and drinking alcohol will increase the risk of hypoglycemia and raise the risk of lactic acidosis, drinking too much alcohol will result in a higher risk. Ask your doctor if you are consuming alcohol while taking Metformin.

Surgical or radiological procedure:

It would help if you stopped taking Metformin before the surgery. This leads to Metformin slowing down your body and raising the risk of lactic acidosis. Inform your doctor when you take drugs before the procedure.

List down who you should not take:

Like all medications, Metformin is not suitable for every person. It is high in vulnerable side effects, so the following people are not allowed to take Metformin.

  • People with stage 4 or 5 kidney disease
  • Type 1 diabetes people
  • Older adults with prediabetes
  • People with Diabetic Ketoacidosis
  • People with certain liver diseases.

Your doctor or health care provider will decide if Metformin works for you, and have a concern with your doctor before using this medication.
Side effects of Metformin

Male suffering from Side effects

Metformin side effects are not known for different people of the same sex.
A study states that people who have been assigned to consume Metformin have lower testosterone levels (it is a male hormone linked to sexual health).

Another factor is erectile dysfunction. A person with type 2 diabetes is more likely to cause ED if their blood sugar is not under control. If the person is overweight or obese, are more at risk of developing Erectile dysfunction. Before starting Metformin, you should consult your doctor if you develop ED symptoms.

Women suffering from Side effects:

Metformin side effects are common regardless of gender. There is a condition that people who menstruate may notice different side effects than people who do not Menstruate.

Metformin is used for the treatment of polycystic ovary syndrome. Depending on the symptoms, your doctor will provide this medication. It Could be a first or second choice of drugs. Studies show Metformin will help 50% to 70% of people with irregular bleeding.

Digestive Issues:

There are 25% of people with diabetes have trouble with bloating, gas, diarrhea, belly pain, and constipation. The only way to treat these side effects is to take a medication at a lower dose at the start.

Vitamin B12 Deficiency:

Due to the lack of B12, your risk of peripheral neuropathy starts increasing. This leads to numbness or Tingling in your feet and legs. Therefore, it is a risk of diabetes, so it is advised to check your B12 level regularly by eating natural eggs and dairy products.

Lactic Acidosis:

A small group of people who are taking the drug will suffer from lactic acidosis. It is a chemical that your muscles and red blood cells produce naturally. People with kidney disorders will experience more and can’t clear the Metformin from the body.

Other side effects

  • Stomach pain
  • Hot burn
  • Bloating
  • Diarrhea
  • Constipation
  • Weight loss
  • Headache
  • Heartburn

How to manage Metformin side effects

It is always necessary for you to know how to manage a medicine’s side effects.

Always Take your drug with your meal:

While taking a drug with your food, you are more likely to experience fewer symptoms. If you take tablets once daily, you should take them with your biggest meal. If you take it twice a day, try to take it at the opposite end of the day.

Switch To Extended Release (ER) Metformin:

Usually, the people who have been prescribed Metformin get the immediate release (IR) version. They are more likely to experience an upset stomach. Due to the extended out of the tablet, which is coating the release of the medication slowly and leads to less stomach upset

Starting with a lower dose:
At the initial stage, you can go with a lower dose; it may work to reduce the side effects. The initial starting dose of 500 mg is recommended.

Metformin Interactions

Drug interactions are when a new drug is added to certain medications, herbals, and foods. Some medicines may develop adverse side effects due to unwanted reactions in your body. Before interacting with the drugs, let your doctor/ health care provider know about the supplements you are taking.

Some Possible Drug interactions are,

  • Digoxin
  • Cimetidine
  • Oral Contraceptive
  • Ranitidine
  • Morphine
  • Vancomycin
  • Phenytoin
  • Beta-blockers
  • Calcium channel blockers
  • Diuretics

Final Words From AzDrug

As of now, we have come to understand that the Drug Metformin is related to constipation. Metformin is used to treat people with high sugar levels in their bloodstream.

More than 3.9 million people are affected by diabetes. It is a widely used drug all over the world. When it comes to constipation, people with Type 1 and Type 2 are at higher risk of developing constipation due to certain medical conditions, So always consult your doctor if you are experiencing severe side effects.

What should you avoid when on metformin medication?

While taking Metformin, avoid carbonic anhydrase inhibitors, corticosteroid drugs, blood pressure medication, oral contraceptives, and antipsychotic drugs.

Benefits of Metformin at night

If you consume it during bedtime, it works on the Glucophage retard, and helps control diabetes by reducing morning hyperglycemia.

How long does Metformin 500 last in your system?

The drug results will not show immediately within 48 hours. It is noticeable after taking the medication. Generally, it stays in your system for 96.8 hours, 4-5 days.

Disclaimer: Please see your healthcare practitioner for any medical queries or concerns. Peer-reviewed research and information from medical societies and government agencies are used to support the articles in Health Guide. They are not, however, a replacement for expert medical advice, diagnosis, or treatment.

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