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Terms Of Use

METFORMIN

Brand Name(s) : Glucophage, Glucophage SR, Metsol, Competact (in combination with pioglitazone), Eucreas (in combination with vildagliptin)
Warnings
Uses
Side Effects
Precautions
Interactions
Overdose

METFORMIN WARNINGS

Metformin should be used with caution in: the elderly, those on a very low calorie diet or whom are likely to have surgery under general anaesthesia, or those with any liver problems, kidney problems, a heart disorder, or who drink alcohol to excess, those with sodium restricted diet

It should not be used in: women who are breastfeeding, patients with any form of kidney problem or any conditions with the potential to alter renal function such as dehydration, severe infection, shock, or anyone having an injection of contrast agents containing iodine into their muscles; those with severe liver problems, are an alcoholic or are drunk; anyone with a condition that may result in a lack of oxygen in body organs (e.g. heart failure, recent heart attack, shock, or conditions that cause severe breathing difficulties); diabetic ketoacidosis (a life-threatening complication of diabetes that can occur when glucose is not available as a fuel source and fat is used instead, resulting in the accumulation of ketones resulting from the breakdown of fat); or diabetic comatose (unable to wake) or precomatose (leading up to coma) states.

Treatment with metformin can cause a serious condition called lactic acidosis (the accumulation of too much acid in the blood), which requires urgent hospital treatment. Its symptoms include muscle cramps, abdominal pain, breathlessness and a feeling of being very weak and unwell. Tell your doctor immediately if you develop these symptoms. There is an increased risk of lactic acidosis in people with kidney disease and in prolonged fasting, excessive alcohol intake and poor blood sugar control.

Also see list of precautions and interactions.

STORAGE

Store below 25°C

METFORMIN USES

Metformin is used to treat diabetes.

It is a member of a class of drugs called anti-diabetics, and more specifically the sub-group called biguanides.

In general, this drug is used to treat type 2 diabetes, particularly in patients who are overweight, and when diet and exercise alone does not result in adequate control of blood glucose levels.

Benefits of being on this drug include a reduction in the incidence of some complications which are often associated with diabetes, as well as the likelihood of premature death (particularly death associated with diabetes) and likelihood of a heart attack.

Listed below are the typical uses of metformin.

  • Treatment of type 2 diabetes mellitus, which occurs when the level of glucose (sugar) in the blood becomes higher than normal.

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.

HOW TO USE/TAKE

How often do I take it?

  • This medication is available as tablets, oral solution and powder (for suspension in water), all of which should be taken orally, every day, during or just after meals. Tablets should be taken with a glass of water. Modified release tablets should be swallowed whole and should not be crushed or chewed.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take some time before you notice any benefits of this drug.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy and use of certain interacting medicines.

Do I need to avoid anything?

  • Avoid drinking alcohol. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.

METFORMIN SIDE EFFECTS

Most common:

Rarely:

  • Lactic acidosis (symptoms of deep and rapid breathing, vomiting, stomach pain, feeling of being very weak and unwell)
  • Itching
  • Redness of the skin
  • Itchy skin rash

If any of these persist or you consider them severe then inform your doctor.

Tell your doctor immediately if you develop any of the following symptoms: lactic acidosis (symptoms of deep and rapid breathing, vomiting, stomach pain, feeling of being very weak and unwell).

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.

METFORMIN PRECAUTIONS

Before taking metformin, tell your doctor or pharmacist if you are allergic to it; or to other anti-diabetic agents; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: a severe infection, any form of heart or lung disease, diabetic ketoacidosis (a life-threatening complication of diabetes that can occur when glucose is not available as a fuel source and fat is used instead, resulting in the accumulation of ketones resulting from the breakdown of fat) or are in a diabetic comatose (unable to wake) or precomatose (leading up to coma) state, or are about to undergo a procedure involving the injection of contrast medium (containing iodine) into the muscles or an operation, including dental treatment, that involves an anaesthetic.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: any history of heart disease, liver or kidney problems, any condition that may result in a lack of oxygen in body organs (e.g. heart failure, recent heart attack, shock, or conditions that cause severe breathing difficulties), or drinking alcohol to excess.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Yes. Do not drink alcohol whilst taking metformin.

Pregnancy and breastfeeding - please ensure you read the detailed information below

PREGNANCY

Metformin is not safe to take during pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.

BREAST FEEDING

Metformin is not safe to take if you are breastfeeding. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.

METFORMIN INTERACTIONS

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • Iodinated contrast agents (used before radiography to enhance the visibility of blood vessels, organs, cancers etc.)

If you are currently using any of these medications, tell your doctor or pharmacist before starting metformin.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

This information does not contain all possible interactions. Therefore, before using metformin, tell your doctor or pharmacist of all the products you use.

METFORMIN OVERDOSE

A large overdose of metformin may lead to lactic acidosis (with symptoms of deep and rapid breathing, vomiting, stomach pain, feeling of being very weak and unwell), which is a medical emergency and must be treated in hospital.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of metformin or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.

MISSED DOSE

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited or TicTac Communications Ltd. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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