Metformin – action, dosage, contraindications and side effects. Does metformin help with weight loss?

Proven content

Metformin is an active substance that is commonly used in antidiabetic drugs aimed at patients with type 2 diabetes. Although metformin treatment is implemented as the first-line treatment of diabetes, studies indicate a wider therapeutic potential of this drug. How does metformin work? What are the rules of its use and possible side effects?

Metformin – a drug for diabetes

Metformin is a drug belonging to the derivatives of biguanide, i.e. a substance present in rutwica, a plant used in traditional herbal medicine. The medical use of metformin became possible thanks to its discovery and confirmation hypoglycaemic properties. Currently, this active substance is mainly used as a first-line treatment in patients with type 2 diabetes. Another indication is polycystic ovary syndrome (PCOS). Medicinal preparations with metformin are available on prescription.

How does metformin work?

Metformin is commonly used in type 2 diabetes medications, which are however only available on the prescription of a doctor. Before using these products, it is necessary to consider the contraindications and determine the appropriate treatment regimen for a given patient. In the treatment of type 2 diabetes, metformin works by lowering blood glucose levels through three mechanisms:

1. reducing the production of glucose by the liver;
2. lowering glucose absorption in the gut;
3. increased peripheral glucose uptake.

The antihyperglycemic properties of metformin allow for lowering of the patient’s fasting and postprandial glucose levels. There is no increase in insulin secretion, which helps to avoid hypoglycaemia. Nowadays, drug therapies are implemented not only in the case of type 2 diabetes, but also in the case of metabolic syndrome (abdominal obesity, lipid disorders), insulin resistance, problems with glucose tolerance or polycystic ovary syndrome.

Although it is the aforementioned effect of metformin that comes to the fore in clinical practice, some studies show that this active substance may have a broader therapeutic effect. Therefore, the greater potential of the drug and the possibility of using it for the treatment of other diseases (e.g. obesity, non-alcoholic steatohepatitis), cardiovascular prophylaxis and anti-aging therapies or neoplastic processes are indicated.

Metformin – dosage

In the treatment of type 2 diabetes, the dosage of metformin is adjusted according to the blood glucose level and the age of the patient. Possible renal dysfunction, other medications taken or accompanying diseases are also taken into account. For adults in Europe, 3000 mg of metformin is considered the maximum daily dose (unless there are specific contraindications). In European countries, the average daily dose recommended for patients is in the range of 1200–1900 mg of metformin.

Metformin is taken orally, usually in 2-3 divided doses. It is recommended to use the preparation during or immediately after a meal to improve its tolerance. The drug is available in tablets (also coated and sustained release) with different active substance content. Medicines with metformin should be taken as prescribed by your doctor.

Also read: What might be the risk of stopping metformin use?

Metformin – contraindications

Before taking medications with metformin read the contraindications to their use. The patient should inform the doctor about diseases and conditions that may be associated with health risks while taking this substance. Metformin should not be taken by people:

1. with hypersensitivity to metformin or other substances in the composition of the drug;
2. with renal failure (with creatinine clearance <50 ml / min);
3. with heart failure or respiratory failure;
4. with hypoxia;
5. who have hypoglycaemia;
6. after metabolic acidosis, including lactic acidosis or ketoacidosis;
7. affected by vascular complications of diabetes;
8. with liver failure;
9. alcohol abusers;
10. suffering from complications of diabetes such as dehydration or ketosis;
11. with serious infections;
12. pregnant or breastfeeding;
13. with deficiencies of vitamin B12 and iron;
14. in the perioperative period;
15. after taking intravenous contrast agents – wait at least 48 hours;
16. taking phenothiazines, barbiturates or other drugs that lower the redox potential of cells.

A relative contraindication is also the use of metformin by elderly patients (over 75 years of age).. If the doctor considers that the patient’s health condition allows it, it is possible, however, to start the treatment with the selected drug with metformin. Caution and compliance with the doctor’s recommendations are also recommended in the case of children, especially children before adolescence.

Metformin – side effects

As with other drugs, the use of metformin may also cause side effects in some patients. Although the substance is generally well tolerated, the person being treated may experience gastrointestinal symptoms including abdominal pain, nausea, diarrhea, vomiting or a noticeable metallic taste in the mouth. These symptoms appear at the beginning of treatment (during the first 6 or 10 weeks) and usually disappear with time.

Another possible side effect of metformin is a deterioration in the absorption of B vitamins, which can lead to vitamin B12 deficiency and, consequently, anemia. In such a situation, it may be appropriate vitamin B12 supplementation and continued use of the therapeutic agent.

A rare but dangerous side effect that metformin can have is lactic acidosis. It is a serious and life-threatening condition, but the risk of this complication is similar to that of other medicines used to treat diabetes. It should be remembered that a higher probability of lactic acidosis appears if metformin is dosed inconsistently with the instructions or if the patient is contraindicated (kidney, liver or heart diseases).

Metformin and slimming

Excessive body weight in the form of obesity is a significant health problem classified as a civilization disease. Obesity is one of the risk factors for type 2 diabetes and is therefore also common in already diagnosed patients. A reduced insulin sensitivity is also observed in obese people. Studies show that metformin increases insulin sensitivity in this group – both in obese people with and without diabetes.

In this case, the effect of the drug results from increasing the feeling of fullness, and thus reducing the appetite and the amount of food consumed. Increased weight reduction in obesity therefore appears to be possible with the combination of a proper diet and the use of metformin.

Metformin treatment is considered not only in adults with obesity and diabetes, but also in adolescents suffering from problems with maintaining a healthy body weight, if other methods of losing weight do not give the expected effect. In the case of young people, however, the drug is primarily to play a preventive role – to prevent insulin resistance and the metabolic syndrome. The basic form of fighting overweight and obesity is introducing changes in nutrition and increasing physical activity.

Also read: Can metformin be used for weight loss?

Metformin in the treatment of polycystic ovary syndrome (PCOS)

One of the indications for the implementation of metformin therapy is polycystic ovary syndrome, also known as polycystic ovary syndrome. Treatment has a positive effect on weight reduction, especially in obese women, which has a positive effect on the hormonal balance and the chances of getting pregnant. Reductions in cholesterol, triglycerides and BMI, as well as reductions in diastolic blood pressure, have been observed with PCOS treatment with metformin.

Metformin – can it be a cure for aging?

Research is also underway on metformin and its anti-aging effects. The active substance in question increases the activity of the AMPK enzyme, which may slow down cell death. If the results of further research are positive, it is considered to extend the use of the drug to patients with diseases such as progeria, Alzheimer’s disease and Huntington’s chorea.

Metformin – anti-cancer properties

As it turns out, metformin is a much more versatile drug than it could have been assumed at the beginning. The cheap and widely used agent also has a tendency to have an anti-cancer effect. In patients with diabetes, a decrease in the risk of developing hepatoblastoma and colorectal cancer has been noticed. There are also indications that metformin reduces the risk of malignancies, including lung cancer, pancreatic cancer, hepatocellular carcinoma, as well as prostate, breast and endometrial cancer.

Metformin – cardioprotection and liver protection

Patients with diabetes taking metformin treatment less often suffer from cardiovascular complications related to this disease – it lowers blood pressure, LDL cholesterol, leptin, fasting insulin, as well as the amount of abdominal fat (typical for abdominal obesity). Therefore, the risk of macroangiopathy and myocardial infarction is reduced.

The beneficial effects of metformin have also been noticed in the context of non-alcoholic fatty liver disease (NAFLD). Subsequent reports indicate that the drug could be suitable for the supportive treatment of this disease, as it may reduce the accumulation of fat in the liver.

Medicines containing metformin

Examples of drugs with metformin are Avamina, Metformax, Siofor, Glucophage and Formetic. These products are dispensed by the pharmacist after the patient shows the prescription.

Find out more:

1. How many drugs with metformin are sold in Poland?
2. Gestational diabetes – causes, symptoms, treatment and prevention
3. SARS-CoV-2 coronavirus and diabetes. Position of the Polish Diabetes Society