What is Metformin?
Metformin is a widely used oral antidiabetic medication, often prescribed as the first-line treatment for type 2 diabetes. It works by reducing the amount of sugar your body absorbs from food, decreasing the amount of sugar produced by your liver, and increasing your body's response to the insulin that it makes naturally [1].
Metformin's primary mechanisms of action include suppressing hepatic glucose production, mainly hepatic gluconeogenesis, and enhancing peripheral tissue insulin sensitivity [2]. It also increases the plasma concentrations of the glucose-lowering gut incretin hormone glucagon-like peptide-1 (GLP-1), which may contribute to its glucose-lowering effect [3].
Uses of Metformin
As discussed, Metformin is primarily known for its role in managing type 2 diabetes by decreasing plasma glucose levels [4, 5]. It has been in use for over six decades and continues to be the preferred drug for newly diagnosed type 2 diabetes mellitus [6].
Hormonal disorders
Beyond its primary use, Metformin is beneficial in several other medical conditions. It is used in the treatment of polycystic ovarian syndrome, a hormonal disorder common in women of reproductive age [7].
Cancer prevention
In addition to these uses, Metformin is being investigated for its potential in preventing various types of cancer, including breast, endometrial, bone, colorectal, and melanoma [8]. It has also shown promise in the prevention and improvement of survival in patients suffering from hepatocellular carcinoma, a type of liver cancer [9].
Neuroprotective effects
Metformin has also been studied for its neuroprotective effects and potential therapeutic benefits for mild cognitive impairment and Alzheimer's disease. It has been shown to improve mental function and reduce the incidence of dementia [9].
Other uses of Metformin
Another condition that Metformin has been shown to slow the progression of is Duchenne muscular dystrophy, a genetic disorder characterised by progressive muscle degeneration and weakness [9].
In terms of infectious diseases, tuberculosis (TB) and coronavirus disease (COVID-19) are among the conditions suggested to be affected by Metformin [9].
The beneficial effects of Metformin in cardiovascular diseases have also been reported [9].
Regarding renal function, studies have shown that daily oral administration of Metformin could ameliorate kidney fibrosis and normalise kidney structure and function [9].
Despite the wide range of potential uses, it's important to note that many of these are still under investigation, and more extensive studies are needed to confirm these additional benefits [3].
Side effects of Metformin
Metformin is generally considered safe and effective. However, it can cause various side effects, primarily affecting the digestive system [10, 11].
Mild side effects:
Side effects like:
- diarrhoea,
- nausea, v
- omiting,
- gas,
- indigestion,
- abdominal discomfort,
- and headache
are common when using Metformin. These symptoms are usually mild and tend to go away over time. However, if they persist or become severe, seeking medical attention is important [12, 13, 14, 15].
Weight loss is another side effect that some people may experience while taking Metformin. This is typically due to a loss of appetite rather than a direct effect of the medication [10, 13].
In some cases, Metformin can lead to a deficiency in vitamin B12, especially with long-term use. Symptoms of this deficiency include low energy, muscle weakness, loss of appetite, and tingling or numbness in the hands or feet [10, 13, 16].
Hypoglycemia, or low blood sugar, is a potential side effect when Metformin is used in combination with other diabetes medications. Symptoms can include dizziness, sweating, increased heart rate, confusion, blurry vision, headache, hunger, and feeling jittery [10, 13, 16].
Severe side effects
One of the most severe but rare side effects of Metformin is lactic acidosis. This condition, characterised by the buildup of lactic acid in the blood, can be life-threatening. Symptoms include tiredness, weakness, unusual muscle pain, trouble breathing, unusual sleepiness, stomach pains, nausea, vomiting, dizziness, lightheadedness, and slow or irregular heart rate [10, 11, 13, 16].
Does fatigue due to Metformin go away?
Fatigue is a common side effect when starting Metformin, but it usually goes away over time as your body adjusts to the medication. In most cases, fatigue and other gastrointestinal side effects like nausea and diarrhoea are mild and subside within a few days to a few weeks [17].
In some cases, the fatigue could be a sign of a more serious side effect like lactic acidosis, which requires immediate medical attention.
If the fatigue persists or worsens, you must consult your doctor. They can help determine the best action to manage your symptoms and ensure the medication works effectively for you.