Taking daily medication can feel routine, especially when it helps keep a chronic condition under control.
For many people living with type 2 diabetes, treatment becomes part of normal life, something rarely questioned once it begins.
Metformin is one of the most widely prescribed diabetes drugs in the world, used by an estimated 120 million people.
It is recommended as a first-line treatment by health authorities such as the NHS and supported by organisations including Diabetes UK.
The medication lowers blood sugar by improving how the body responds to insulin and reducing glucose production in the liver.
It is also sometimes prescribed during pregnancy for gestational diabetes and for women with polycystic ovary syndrome.
Common side effects
Although considered safe and effective, metformin often affects the digestive system. Frequently reported reactions include nausea, diarrhoea, stomach pain, reduced appetite and a metallic taste in the mouth. Health guidance recommends taking it with meals to reduce these symptoms.
Long-term use, particularly at higher doses, has been linked to vitamin B12 deficiency.
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According to the NHS, low B12 levels can lead to extreme tiredness, tingling sensations, mouth ulcers and pale skin. Routine blood tests can help detect this early.
Rare but serious risks
Severe complications are uncommon but require urgent medical attention. These include lactic acidosis, a rare condition involving breathing difficulties, weakness and feeling unusually cold. Liver problems and severe allergic reactions may also occur.
Metformin is not suitable for everyone, particularly people with significant kidney or liver disease or heavy alcohol use.
Patients are advised to consult healthcare professionals before making any changes to treatment.
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Sources: LADbible, NHS og Diabetes UK
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