Metformin tablet – an ideal medicine for Diabetes

Posted On January 10, 2021January 23, 2021

What’s up guys! Today, I am going to review a popular drug which is commonly prescribed for diabetes i.e., Metformin tablet.

Metformin is the most widely used antidiabetic medicine. It is officially approved from the FDA in 1994.

As you know, diabetes is a common disorder which increases your blood sugar level and it is one of the leading causes of death.

The surprising thing is that about 422 million people are already diagnosed with diabetes worldwide, according to WHO. It is such a huge number and it is not going end of the story. If current trends continue the number could be countless.

But you don’t need to worry, there are various oral hypoglycemic agents which help to control your blood glucose level.  Among all antidiabetic drugs, metformin is considered as first-line medicine to treat type 2 diabetes.

As per ADA (American diabetes association) – the meal planning, weight loss and exercise are the first steps to control high blood glucose level. If you are unable to manage your diabetes from diet and exercise. You will have to add this wonderful drug – metformin in your daily life.

In this article, I am going to share a complete guide on Metformin tablet. So, without further delay, let’s know about this medicine.

What is metformin tablet used for?

Metformin is an oral hypoglycemic agent (or antidiabetic medication) which used to treat type 2 diabetes mellitus and prediabetes. It also has the potential to treat PCOS (polycystic ovary syndrome) but it is not officially approved from FDA for PCOS.

Usually, metformin is the drug of choice if you have recently developed type 2 diabetes mellitus. It works well when used with diet and exercise.

What does metformin do exactly?

Metformin is a biguanide class of drug that helps to reduce your blood glucose level in three ways –

1. Reduce gluconeogenesis (gluconeogenesis means the formation of new glucose) –

it decreases the absorption or delays the absorption of your new glucose molecule in the intestine so that less glucose in the blood.

2. Reduce hepatic glycogenolysis (glycogenolysis means breaks down of glycogen into glucose) –

It reduces the breakdown of glycogen to glucose. It helps to decrease glucose formation in the liver and hence decrease the transport of glucose from the liver to blood.

3. Reduce insulin resistance (insulin resistance means cells stop responding to insulin) – It helps to increase sensitivity in your muscles and makes your body respond well to insulin.

When should I take my metformin tablet?

Your doctor may start metformin from 500 mg twice or three times a day. The dose of your metformin could be increased depending upon the severity of your disease.

The maximum permissible dose of metformin is 2.5gm/day (or 2500 mg/day). You should not take more than 2.5gm of metformin because it may cause lactic acidosis that could be fatal.

You should always take your metformin tablet with food or after food to minimise gastric side effects.

Is Metformin Safe?

According to ADA, Metformin is the preferred antidiabetic drug for type 2 diabetes patients. It is absolutely safe in adults, children over 10 years and older patients.

There is also evidence suggests that metformin has a cardioprotective role. It is the only antidiabetic agent proved to reduce cardiovascular risk. So, if you are struggling with heart disease with type 2 diabetes, it will help to decrease your cardiovascular events (like heart attacks).

It is also safe in mild to moderate kidney impairment function but contraindicated in chronic kidney failure.

A recently published article in the lancet healthy longevity, January 2021 assessed the data of metformin and risk of mortality in female patients hospitalised with COVID-19 (Coronavirus disease).

It was a retrospective cohort study. It concluded that metformin significantly reduced mortality in type-2 diabetes female patients who were hospitalised due to COVID-19.

Metformin helps to reduce inflammation proteins like TNF-alpha and other inflammatory adipokines that appear to make COVID-19 worse.

It also has some other crucial benefits –

• it does not cause weight gain
• it does not cause hypoglycemia like other oral hypoglycemic medication (unless combined with other antidiabetic drugs)

Hence, it is safe, effective and well-tolerated medicine for type 2 diabetes patients.

What are the side effects of metformin?

The most common side effects of Metformin are gastric disturbances. During the initiation of therapy, you may suffer –

• diarrhoea
• nausea or vomiting
• bloating
• stomach pain
• heartburn
• constipation
• loss of appetite
• unpleasant metallic taste in the mouth

Metformin also causes lactic acidosis. It rarely happens but it is the most serious side effect of Metformin. Due to this, metformin has a black box warning from US-FDA.

In lactic acidosis, lactate built up in your body which is difficult to eliminate. Lactic acidosis may cause hypotension (low blood pressure), hypothermia (decreased body temperature) and eventually death.

It could be more fatal if you are already compromised with kidney and liver problem.

In a recent study, it has seen metformin cause Vitamin B12 deficiency. If you are taking metformin for a long time, it may increase the risk of low vitamin B12 level, particularly in anaemic or peripheral neuropathy patients.

Why was metformin taken off the market?

According to review literature published in the Journal of the American Medical Association (JAMA), 2019 suggested metformin has the biggest concern over lactic acidosis that’s why it was taken off the US market.

But later on, it was reintroduced in 1995 because it has been proven effective in lowering blood glucose level. It has also proven safety data in other circumstances.

So, you don’t need to panic about its side effects. Metformin rarely causes lactic acidosis only in extreme overdose (>2500 mg/day).

How does metformin affect pregnancy?

Metformin drug comes in category-B. Usually, Category-B drugs are considered safe in pregnancy.

An exploratory case-control study published in BMJ (British Medical Journal, 2018) found no evidence for increased risk of birth defect during metformin therapy in pregnancy.

You can use metformin in pregnancy but it is not a preferable drug. Insulin injections are considered gold standard treatment (drug of choice) in Pregnancy.

Who should not take metformin?

You should not take metformin in the following circumstances –

1. You should stop metformin if your blood creatinine level is more than 150 micromols/l (normal range 74.3 to 107 micromoles per litre).

2. You should strictly avoid if you are already dealing with chronic liver disease.

3. You should stop metformin therapy 48 hours before if you are going for imaging procedures in iodinated contrast media.

According to a study, contrast media procedure with metformin can be worsening the kidney condition that induces nephropathy.

What medicine works best with metformin?

Usually, metformin tablet comes in two forms – immediate release (normal tablet form) and extended-release (XR, XL, ER) or sustained-release (SR) or control release (CR).

The extended-release tablet is better than the normal tablet. It decreases your dose frequency and reduces the gastric side effects because it slowly releases in your gastrointestinal tract.

The metformin tablet is available in common brands – Glucophage, Glyciphage, Gluconorm SR, Glycomet, Obimet, Cetapin XR.

Metformin tablet works better with some other oral hypoglycemic agent. It is also available in combination with the popular brand name –

• Janumet 50/500 or 50/1000 (the combination of metformin and sitagliptin)
• Galvus Met (the combination of metformin and vildagliptin)
• Kombiglyze XR5mg/1000mg (the combination of metformin and saxagliptin)
• Ziten M (the combination of metformin and teneligliptin)
• Trajenta duo 2.5mg/500mg (the combination of metformin hydrochloride and linagliptin)
• Glycomet GP1 or GP2 (the combination of metformin and glimepiride)
• Diamicron XR MEX 500 (combination of metformin and gliclazide)
• Jardiance Met 12.5mg/500mg or 1000mg (combination of metformin HCL and empagliflozin)
• Glimet (combination of metformin and glipizide)

What medications should not be taken with metformin?

Although, there are no severe interaction with other drugs while metformin treatment. Still, you may require caution or consult your doctor if you are taking –

• Pain-relieving medicines like NSAIDs (Ibuprofen, celecoxib etc.)
• Medicines which increase urine output especially loop diuretics (Furosemide).
• Medicines used in the treatment of hypertension (ACE inhibitors and angiotensin receptor antagonists)
• Certain medicines used to treat asthma (beta 2 agonist such as salbutamol, terbutaline)
• Corticosteroids like prednisolone

There are some drugs (such as verapamil, rifampicin, cimetidine, dolutegravir, ranolazine, trimethoprim, vandetanib, isavuconazole, crizotinib, olaparib) which may reduce the kidney function.

These drugs may increase the metformin concentration in your blood. So, you may require close monitoring of your kidney function especially if you are kidney disease patient.

Conclusion –

We have seen a various scientific study of Metformin tablet. It is such a great medicine with minimal significant side effects.

More or less, metformin is quite safe, with good efficacy, well-tolerated and valuable medicine for type 2 diabetic patient.

So, you must consider this ideal antidiabetic medicine to consult your doctor.

I hope you would have found this post to be informative. Share it in social media to spread awareness.

Also Read – 

• Blood glucose level

• Treatment of diabetes