Patient leaflet - Glyformin/metformin
1. WHAT GLYFORMIN IS AND WHAT IT IS USED FOR
Glyformin belongs to a group of medicines known as anti- diabetics. It is used in diabetes occurring in middle age when diet alone has failed. It is also used in obese diabetic patients who are not well controlled by insulin, but who are dependent on insulin and may therefore occasionally benefit when Glyformin is used together with insulin.
If you are not sure why you have been prescribed Glyformin then please ask your doctor.
2. WHAT YOU NEED TO KNOW BEFORE YOU TAKE GLYFORMIN
Do not take GLYFORMIN
- If you are allergic (hypersensitive) to metformin Hydrochloride or any of the other ingredients of this medicine (listed in section 6).
- If you have uncontrolled diabetes, with, for example, severe hyperglycaemia (high blood gIucose), nausea, vomiting, diarrhoea, rapid weight loss, lactic acidosis (see "Risk of lactic acidosis" below) or ketoacidosis. Ketoacidosis is a condition in which substances called 'ketone bodies' accumulate in the blood and which can lead to diabetic pre-coma. Symptoms include stomach pain, fast and deep breathing, sleepiness or your breath developing an unusual fruity smell.
- If you lost too much water from your body (dehydration), such as due to long-lasting or severe diarrhoea, or if you have vomited several ti mes in a row. Dehydration may lead to kidney problems, which can put you at ri sk for lactic acidosis (see 'Warnings and precautions').
- If you have a severe infection, such as an infection affecting your lung or bronchial system or your kidney. Severe infections may lead to kidney problems, which can put you at risk for lactic acidosis (see 'Warnings and precautions').
- If you are treated for acute heart failure or have recently had a heart attack, have severe probIems with your circuIation (such as shock) or have breathing difficulties. This may lead to a lack in oxygen supply to tissue which can put you at risk for lactic acidosis (see 'Warnings and precautions').
Also tell your doctor or pharmacist if you are allergic to any other substances such as foods, preservatives or dyes.
Because the presence of other medical problems may affect the use of Glyformin, make sure to tell your doctor if you have had any of the following:
- Liver disease
- Kidney disease, severely reduced kidney function
- Cardiac failure, or recent coronary thrombosis
- Lung impairment
- Alcoholism (either chronic or acute)
- Severe infection
- Blocking of the blood vessels of the extremities, particularly the legs, known as peripheral vascular disease.
- Dehydration.
- Disturbances in the metabolic state of the blood (lactic acidosis, hypoxaemia).
If you develop any new medical problems while using this medicine, check with your doctor or pharmacist.
Make sure you ask your doctor for advice, if:
- you need to have an examination such as X-ray or scan involving the injection of contrast medicines that contain iodine into your bloodstream
- you need to have major surgery
- you must stop taking Glyformin for a certain period of time before and after the examination or the surgery. Your doctor will decide whether you need any other treatment for this time. It is important that you follow your doctor's instructions precisely.
Warnings and precautions
Risk of lactic acidosis
Glyformin may cause a very rare, but very serious side effect called lactic acidosis, particularly if your kidneys are not working properly. The risk of developing lactic acidosis is also increased with uncontrolled diabetes, serious infections, prolonged fasting or alcohol intake, dehydration (see further information below), liver problems and any medical conditions in which a part of the body has a reduced supply of oxygen (such as acute severe heart disease).
If any of the above apply to you, talk to your doctor for further instructions.
Stop taking Glyformin for a short time if you have a condition that may be associated with dehydration (significant loss of body fluids) such as severe vomiting, diarrhoea, fever, exposure to heat or if you drink less fluid than normal. Talk to your doctor for further instructions.
Stop taking Glyformin and contact a doctor or the nearest hospital immediately if you experience some of the symptoms of lactic acidosis, as this condition may lead to coma.
Symptoms of lactic acidosis include:
- vomiting
- stomach ache (abdominal pain)
- muscle cramps
- a general feeling of not being well with severe tiredness
- difficulty in breathing
- reduced body temperature and heartbeat
Lactic acidosis is a medical emergency and must be treated in a hospital.
If you need to have major surgery you must stop taking Glyformin during and for some time after the procedure. Your doctor will decide when you must stop and when to restart your treatment with Glyformin.
Glyformin on its own does not cause hypoglycaemia (a blood glucose level which is too low). However, if you take Glyformin together with other medicines to treat diabetes that can cause hypoglycaemia (such as sulphonylureas, insulin, meglitinides), there is a risk of hypoglycaemia. If you experience symptoms of hypoglycaemia such as weakness, dizziness, increased sweating, fast heart beating, visions disorders or difficulty in concentration, it usually helps to eat or drink something containing sugar.
During treatment with Glyformin, your doctor will check your kidney function at least once a year or more frequently if you are elderly and/or if you have worsening kidney function.
Talk to your doctor promptly for further instructions if :
- You are known to suffer from a genetically inherited disease affecting mitochondria (the energy-producing components within cells) such as MELAS syndrome (Mitochondrial Encephalopathy, myopathy, Lactic acidosis and Stroke-like episodes) or Maternal inherited diabetes and deafness (MIDD).
- You have any of these symptoms after starting metformin: seizure, declined cognitive abilities, difficulty with body movements, symptoms indicating nerve damage (e.g. pain or numbness), migraine and deafness.
Other medicines and GLYFORMIN
If you need to have an injection of a contrast medium that contains iodine into your bloodstream, for example in the context of an X-ray or scan, you must stop taking Glyformin before or at the time of the injection. Your doctor will decide when you must stop and when to restart your treatment with Glyformin.
Tell your doctor or if you are taking, have recently taken or might take any other medicines. You may need more frequent blood glucose and kidney function tests, or your doctor may need to adjust the dosage of Glyformin. Your doctor will be able to identify medicines which you should not take with Glyformin.
Tell your doctor or pharmacist if you are taking any of the following:
- Cimetidine (used to treat stomach ulcers), which can increase blood concentrations of meformin.
- Alcohol, which will increase the blood sugar lowering effects of meformin.
- Anti-coagulants such as warfarin (blood-thinners).
- Sulphonylureas
- Insulin
- Medicines which increase urine production (diuretics)
- Medicines used to treat pain and inflammation (NSAID and COX-2-inhibitors, such as ibuprofen and celecoxib)
- Certain medicines for the treatment of high blood pressure (ACE inhibitors and angiotensin II receptor antagonists)
- Beta-2 agonists such as salbutamol or terbutaline (used to treat asthma)
- Corticosteroids (used to treat a variety of conditions, such as severe inflammation of the skin or in asthma)
- Medicines that may change the amount of Glyformin in your blood, especially if you have reduced kidney function (such as verapamil, rifampicin; cimetidine, dolutegravir, ranolazine, trimethoprime, vandetanib, isavuconazole, crizotinib, olaparib)
- Other medicines used to treat diabetes
Patients receiving Glyformin over prolonged periods should have their levels of Vitamin B12 measured yearly, since levels may be altered by this medicine.
Glyformin with alcohol
Avoid excessive alcohol intake while taking Glyformin since this may increase the risk of lactic acidosis (see section 'Warnings and precautions')
Pregnancy and breast-feeding
If you are pregnant, think you may be pregnant or are planning to have a baby, speak to your doctor in case any changes will be needed to your treatment or monitoring of your blood glucose levels.
This medicine is not recommended if you are breast-feeding or if you are planning to breast-feed your baby.
Driving and using machines
Glyformin on its own does not cause hypoglycaemia (a blood glucose level which is too low). This means that it will not affect your ability to drive or use machines.
However, take special care if you take Glyformin together with other medicines to treat diabetes that can cause hypoglycaemia (such as sulphonylureas, insulin, meglitinides). Symptoms of hypoglycaemia include weakness, dizziness, increased sweating, fast heart beat, vision disorders or difficulty in concentration. Do not drive or use machines if you start to feel these symptoms.
3. HOW TO TAKE GLYFORMIN
Take this medicine by mouth and only in the doses prescribed by your doctor. Do not take more of it, and do not take it more often or for a longer time than your doctor ordered.
Dosages:
Adults: Usually one 500 mg tablet 3 times a day, to be taken with meals. Should control of diabetes be incomplete, a gradual increase in dosage to a maximum of 3 g daily, in divided doses, taken together with meals may be instituted.
This dosage regimen should not be increased above 3 g.
Children: Not recommended.
Elderly: Metformin Hydrochloride, while indicated in the
elderly, should not be used when renal function is impaired.
If you feel that this medicine is not working as well after you have taken it for a short time (1-2 weeks) do not increase the dose, instead check with your doctor.
If you take more GLYFORMIN than you should
If you think you may have taken an overdose of this medicine you must obtain emergency help at once. Go to your doctor or the Accident & Emergency Department of your nearest hospital straight away. Take with you any remaining tablets in the original container so that the medicine can be identified.
If you forget to take GLYFORMIN
If you forget to take your medicine, just carry on with the next dose as normal. Do not take an extra dose to make up for the missed dose. If you are not sure, ask your doctor or pharmacist for advice.
4. POSSIBLE SIDE EFFECTS
Although Glyformin is usually well tolerated, gastro-intestinal disturbances may sometimes occur, and although usually minor they can normally be avoided by taking Glyformin with, or after, food.
Glyformin may cause a very rare (may affect up to 1 user in 10,000), but very serious side effect called lactic acidosis (see section 'Warnings and precautions'). If this happens you must stop taking Glyformin and contact a doctor or the nearest hospital immediately, as lactic acidosis may lead to coma.
Very common: may affect more than 1 in 10 people
- Digestive problems, such as feeling sick (nausea), being sick (vomiting), diarrhoea, bellyache (abdominal pain) and loss of appetite. These side effects most often happen at the beginning of the treatment with Glyformin. It helps if you spread the doses over the day and if you take Glyformin with or straight after a meal. If symptoms continue, stop taking Glyformin and talk to your doctor.
Common: may affect up to 1 in 10 people
- Changes in taste. • Decreased or low vitamin B12 levels in the blood (symptoms may include extreme tiredness (fatigue), a sore and red tongue (glossitis), pins and needles (paraesthesia) or pale or yellow skin). Your doctor may arrange some tests to find out the cause of your symptoms because some of these may also be caused by diabetes or due to other unrelated health problems.
Very rare: may affect up to 1 in 10,000 people
- Lactic acidosis. This is a very rare but serious complication particularly if your kidneys are not working properly. Symptoms of lactic acidosis are non-specific (see section 'Warning and precautions')
- Abnormalities in liver function tests or hepatitis (inflammation of the liver; this may cause tiredness, loss of appetite, weight loss, with or without yellowing of the skin or whites of the eyes). If this happens to you, stop taking Glyformin and talk to your doctor.
- Skin reactions such as redness of the skin (erythema), itching or an itchy rash (hives).
Children and adolescents
Limited data in children and adolescents showed that adverse events were similar in nature and severity to those reported in aduIts.
Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects via the Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.
5. HOW TO STORE GLYFORMIN
Keep this medicine out of the sight and reach of children.
Keep your medicine in a dry place and store below 25ºC, in securely closed containers.
Do not use this medicine after the expiry date which is stated on the label. The expiry date refers to the last day of that month.
Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
6. CONTENTS OF THE PACK AND OTHER INFORMATION
What GLYFORMIN contains
The name of this medicine is Glyformin. Each tablet contains 500 mg of Metformin Hydrochloride BP, together with the following ingredients: Lactose, silicon dioxide, gelatin, sodium starch glycollate, magnesium stearate, hydroxypropylmethylcellulose, ethylcellulose, titanium dioxide (E171), and diethyl phthalate.
What GLYFORMIN looks like and contents of the pack
Glyformin tablets are white, round, bi-convex film-coated tablets, and are available in containers of 28, 30, 50, 56, 60, 84, 100, 250, 500 & 1000 tablets, and in blister packs of 28, 30, 50,
56, 60, 84, 100, 250, 500 & 1000 tablets.
Marketing Authorisation Holder and Manufacturer
The Product Licence Holder of Glyformin is
Chelonia Healthcare Limited,
Boumpoulinas 11, 3rd Floor, Nicosia, P.C.
1060, Cyprus.
The Manufacturer of Glyformin is either:
DDSA Pharmaceuticals Ltd., Chatfield Road, off York Road, London SW11 3SE or
Meridian Healthcare (UK) Ltd., Chatfield Road, off York Road, London SW11 3SE
This leaflet does not contain the complete information about your medicine. If you have any questions or are not sure about anything, ask your doctor or pharmacist who have access to additional information.
This leaflet was prepared in February 2025.