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What Your Doctor Won't Tell You About the Side Effects of Metformin

Updated: Sep 23, 2021


Metformin the only currently available Biguanide antihyperglycemic, marketed under the trade name Glucophage, Glucophage XR, Glumetza, Fortameza, and others. It is believed to be an insulin sensitizer, approved by the United States Food and Drug Administration, used in the treatment of Diabetes mainly Type 2 Diabetes and polycystic ovary syndrome. It is known to be the best medication and the first line in the treatment of Type 2 Diabetes either when used singly or in combination with other drugs made for Type 2 diabetes.

Diabetes Mellitus is a disorder of multiple origins characterized by chronic hyperglycemia with interruption of carbohydrates, proteins and lipid metabolism because of insulin production or action and sometimes both. It is divided into three major types;

  • Type 1 Diabetes Mellitus

  • Type 2 Diabetes Mellitus

  • Gestational Diabetes Mellitus

Other types of diabetes include Maturity-onset Diabete (MODY), Secondary Diabetes Mellitus.


Metformin is the most extensively used oral therapeutic agent for Non-Insulin Dependent Diabetes Mellitus, recording, as given by statistics a global pharmaceutical sale of 464 billion U.S dollars in 2018. As of 2017, the number of times Metformin was prescribed was around 78.6 million times. It has been observed that the use of metformin is leveling off or even falling.

Metformin‘s Statistics in the U.S


In the treatment of Type 2 Diabetes, being an insulin sensitizer, Metformin works by increasing the body’s sensitivity to insulin, it reduces glucose produced by the liver by inhibiting the liver’s glucogenesis. It reduces the absorption of sugars in the gastrointestinal tract and increases the use of glucose by target cells. In hepatocytes, it changes mitochondrial function and actions of AMP-Activated Protein Kinase (AMPK). However, according to diabetes update, metformin does not reduce blood sugar by reducing insulin resistance but acts by activating a gene in the liver thereby stopping the production of glucose.


Metformin has some side effects. It works by basically putting a band-aid over the cause of Type 2 diabetes, by doing so it maintains the disease, and it carries serious side effects that can worsen with long term use.


Metformin is used as a treatment in the form of an adjunct to diet, lifestyle changes, exercise in Type 2 diabetes. It is associated with some serious side effects, which can occur when you take the drug the first time due to its low patients’ adherence rate or when used for a long period of time. Gastrointestinal GI side effects are the most common side effects complained of by patients that were prescribed metformin and a doctor must be consulted if these symptoms are severe.

Some common side effects associated with Metformin are;

  • Lactic acidosis: Metformin can cause a serious and fatal metabolic condition called lactic acidosis. Lactic acidosis is more common in diabetic patients with renal failure due to the kidneys not working at optimal conditions leading to the accumulation of metformin. and it is fatal in about 50% of cases. This condition is characterized by an increased level of acidity in the blood and electrolyte imbalance. This can result in low body temperature, abnormally low blood pressure, and resistant slow heartbeat and ultimately casualty. Prolong use of Metformin will lead to constant accumulation which will further aggravate the disease making it not suitable for long term use.

  • Pregnancy: In premenopausal women not ready for pregnancy having irregular menstrual periods, metformin can increase the chance of pregnancy by enhancing ovulation.

  • On skin: Metformin can cause skin rashes, nail disorder, and increased swelling. it is also possible to cause redness of the skin, severe itching, and urticaria.

  • Diarrhea: Metformin can cause osmotic diarrhea which occurs due to the increase in the concentration of intestinal glucose level due to the reduction in glucose absorption in the intestine.

  • Digestive problems/ Nausea/ Vomiting: Digestive problems, Nausea and Vomiting are the most common side effects when you use metformin for the first time. This is as a result of the release of a hormone named serotonin into the intestine. These side effects tend to occur when you take metformin on an empty stomach, they, however, go away with time, can be minimized by taking the drug with a meal or prescribed dose adjustment. Long-time usage of metformin, however, increases the chance of intensifying these side effects making metformin not desirable as a long term plan for managing Type 2 diabetes.

  • Flatulence Metformin when used in patients having high blood sugar levels, can cause accumulation of excess sugar in the gut which will lead to the overgrowth of normal gut bacteria which promotes the production of gas. Prolonged use of metformin will worsen the condition therefore natural diabetes remedy is a better option.

  • Physical weakness/Asthenia which occurs in the treatment of Type 2 diabetes with metformin when intake is inadequate or exercise is not compensated for with calories.

  • Decreased absorption of Vitamin B12 (Cobalamin) can occur when metformin is being taken for a prolonged time. Vitamin B12 is needed to maintain a healthy blood level. Decreased absorption will then lead to anemia, iron deficiency, and severe neurological problem. Symptoms of Vitamin B12 deficiency include but not limited to nerve damage, dementia-like symptoms, inflammation of the tongue, changes in skin color, etc.

  • Hypoglycemia: Metformin might cause hypoglycemia when prescribed in combination with other drugs used in treating Type 2 Diabetes. This can lead to symptoms such as sudden sweating, shaking, hunger, blurred vision, tingling of hands/feet. Hypoglycemia is a serious condition and must be addressed immediately it happens. It tends to become worse when metformin is used continuously for a very long period of time.

  • Heartburn: a desirable side effect heightened when you take metformin for a very long time.

Less common side effects are abnormal stools, change in taste, difficulty with moving joint pain swollen joints, dizziness, headache, increased hunger which becomes serious due to prolong use of metformin.


The word cure is ascribed to acute diseases such as Pneumonia which can be treated by taking antibiotics. For Type 2 diabetes which is a chronic disease, the right term to use will be reversal rather than than the term cure.

Type 2 diabetes can be reversed through comprehensive, personalized diet changes and lifestyle changes. The absence or presence of type two diabetes is dictated by lifestyle. Even after reversal, with blood sugar levels in a healthy range there is always a chance that the symptoms of Type 2 diabetes will return based on lifestyle. It is possible for some people to go years without trouble controlling their blood glucose as long as they maintain a healthy lifestyle.

The term reversal can also be termed as remission is defined on the following definitions:

  • Partial Remission: this is the maintenance of the blood sugar level below the detectable range without the use of any medication for a period not shorter than one year.

  • Complete Remission: this is the maintenance of normal blood sugar levels in the healthy range for a period not shorter than one year.

  • Prolonged Remission: this is the maintenance of normal blood sugar levels for a period not shorter than five years.


Metformin is one of the most used drugs for Type 2 diabetes and polycystic ovary syndrome, it, however, has some side effects that can be intensified by long-time usage of the drug. This makes it a poor choice as a long term plan for patients suffering from Type 2 Diabetes and Polycystic ovary syndrome who actually want to get better.

Also according to updates in the medical world, metformin does not reduce insulin resistance, it does not address the major cause of diabetes and hence it does not heal the body. When taken for a long period of time it leads to serious side effects which can lead to discontinuation. This discontinuation can be observed in the number of prescriptions (in millions) which dropped from 81.31 in 2016 to 78.6 in 2017 in the United States.

A better plan to go with, for people diagnosed with type 2 Diabetes, is to select healthy lifestyle management programs. The Targeted Lifestyle Program from my online clinic is a year-long physician-supervised program used to help people to recover from Type 2 Diabetes or any other health concerns, it has been producing positive results based on years of experience in dealing with people suffering from disease.

It involves the use of nutritional, dietary and lifestyle changes which are combined with exercise, psycho-spiritual awareness, and meditation, making it a better alternative for people suffering from Type 2 Diabetes who want to remove the danger of serious side effects such as lactic acidosis, heartburn, osmotic diarrhea, flatulence, etc associated with the prolonged use of Metformin and other Type 2 Diabetes drugs that maintain the disease.

Click here to enroll today, so you can get personalized support to get your blood sugars under control.


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