Patient Leaflet Updated 08-Jul-2026 | Tillomed Laboratories Ltd
Metformin Tillomed SR Prolonged-release Tablets
Metformin Tillomed SR 500 mg, 750 mg and 1000 mg Prolonged-release Tablets
(metformin hydrochloride)
1. What Metformin SR is and what it is used for
2. What you need to know before you take Metformin SR
3. How to take Metformin SR
4. Possible side effects
5. How to store Metformin SR
6. Contents of the pack and other information
Metformin SR contain the active ingredient metformin hydrochloride and belongs to a group of medicines called biguanides, used in the treatment of Type 2 (non-insulin dependent) diabetes mellitus.
Metformin hydrochloride is used together with diet and exercise to lower the risk of developing Type 2 diabetes in overweight adults, when diet and exercise alone for 3 to 6 months have not been enough to control blood glucose (sugar). You are at high risk of developing Type 2 diabetes if you have additional conditions like high blood pressure, age above 40 years, an abnormal amount of lipids (fat) in the blood or a history of diabetes during pregnancy.
Metformin hydrochloride is used for the treatment of Type 2 diabetes when diet and exercise changes alone have not been enough to control blood glucose (sugar).
Insulin is a hormone that enables body tissues to take glucose from the blood and to use it for energy or for storage for future use. People with Type 2 diabetes do not make enough insulin in their pancreas or their body does not respond properly to the insulin it does make. This causes a build-up of glucose in the blood which can cause a number of serious long-term problems so it is important that you continue to take your medicine, even though you may not have any obvious symptoms. Metformin hydrochloride makes the body more sensitive to insulin and helps return to normal the way your body uses glucose.
Metformin SR is associated with either a stable body weight or modest weight loss.
Metformin SR is specially made to release the drug slowly in your body and therefore are different to many other types of tablets containing metformin.
Polycystic ovary syndrome (PCOS) is a health condition that affects a woman's hormone levels, menstrual cycle, and ability to have children. Metformin prolonged release is used in women with PCOS to stimulate ovulation (release of an egg from the ovaries), and subsequently the chance of getting pregnant, alone or together with other treatment options.
Risk of lactic acidosis
Metformin SR 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).
Talk to your doctor promptly for further instructions if:
If any of the above apply to you, talk to your doctor for further instructions.
Stop taking Metformin SR 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 Metformin SR 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:
Lactic acidosis is a medical emergency and must be treated in a hospital.
If you need to have major surgery you must stop taking Metformin SR during and for some time after the procedure. Your doctor will decide when you must stop and when to restart your treatment with Metformin SR.
During treatment with Metformin SR, 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.
If you are older than 75 years, treatment with Metformin SR should not be started to lower the risk of developing type 2 diabetes.
You may see some remains of the tablets in your stools. Do not worry - this is normal for this type of tablet.
You should continue to follow any dietary advice that your doctor has given you and you should make sure that you eat carbohydrates regularly throughout the day.
Do not stop taking this medicine without speaking to your doctor.
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 metformin before or at the time of injection. Your doctor will decide when you must stop and when to restart your treatment with Metformin SR.
Tell your doctor 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 Metformin SR. It is especially important to mention the following:
Avoid excessive alcohol intake while taking Metformin SR since this may increase the risk of lactic acidosis (see section 'Warnings and precautions').
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.
Metformin SR can stimulate ovulation (release of an egg from the ovaries), in women who do not ovulate properly.
Beware of an increased chance of becoming pregnant when using Metformin SR.
Metformin SR taken on its own does not cause 'hypos' (symptoms of low blood sugar or hypoglycaemia, such as faintness, confusion and increased sweating) and therefore should not affect your ability to drive or use machinery.
You should be aware, however, that metformin taken with other antidiabetic medicines can cause hypos, so in this case you should take extra care when driving or operating machinery.
This medicine contains less than 1 mmol sodium (23mg) per dosage unit, that is to say it is essentially 'sodium free'.
Your doctor may prescribe Metformin SR for you to take on its own, or in combination with other oral antidiabetic medicines or insulin.
Always take this medicine exactly as your doctor has told you.
You should check with your doctor or pharmacist if you are not sure.
Swallow the tablets whole with a glass of water, do not chew.
Recommended dose
Usually you will start treatment with 500 milligrams Metformin SR daily. After you have been taking Metformin SR for about 2 weeks, your doctor may measure your blood sugar and adjust the dose. The maximum daily dose is 2000 milligrams of Metformin SR.
If you have reduced kidney function, your doctor may prescribe a lower dose.
Normally, you should take the tablets once a day, with your evening meal.
In some cases, your doctor may recommend that you take the tablets twice a day. Always take the tablets with food.
Polycystic ovary syndrome {PCOS)
The usual dose is 1500-2000 mg metformin hydrochloride taken once a day with the evening meal.
You should check with your doctor or pharmacist when to stop taking the medicine.
If you take extra tablets by mistake you need not worry, but if you have unusual symptoms, contact your doctor. If the overdose is large, lactic acidosis is more likely. Symptoms of lactic acidosis are non-specific, such as vomiting, bellyache with muscle cramps, a general feeling of not being well with severe tiredness, and difficulty in breathing. Further symptoms are reduced body temperature and heart beat.
If you experience some of these symptoms, you should immediately seek medical attention, as lactic acidosis may lead to coma. Stop taking Metformin SR immediately and contact a doctor or the nearest hospital straightaway.
Take it as soon as you remember with some food. Do not take a double dose to make up for a forgotten dose.
If you have any further questions of the use of this medicine ask your doctor or pharmacist.
Like all medicines, Metformin SR can cause side effects, although not everybody gets them.
The following side effects may occur:
Metformin SR 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 Metformin SR and contact a doctor or the nearest hospital immediately, as lactic acidosis may lead to coma.
Metformin SR may cause abnormal liver function tests and hepatitis (inflammation of the liver) which may result in jaundice (may affect up to 1 user in 10,000). If you develop yellowing of the eyes and/or skin contact your doctor immediately.
Other possible side effects are listed by frequency as follows:
Very common side effects (may affect more than 1 in 10 people):
Common side effects (may affect up to 1 in 10 people):
Very rare side effects (may affect up to 1 in 10,000 people):
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly 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.
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the carton after “EXP”. The expiry date refers to the last day of that month.
This medicinal product does not require any special storage conditions.
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 to protect the environment.
Metformin SR 500 mg prolonged release tablets are white to off-white coloured, round shaped, biconvex tablets debossed with ‘500’ on one side and plain on other side.
Metformin SR 750 mg prolonged release tablets are white to off-white coloured, capsule shaped, biconvex tablets debossed with ‘750’ on one side and plain on other side.
Metformin SR 1000 mg prolonged release tablets are white to off-white coloured, modified capsule shaped, biconvex tablets debossed with ‘1000’ on one side and plain on other side.
500mg: 20, 28, 30, 50, 56, 60, 84, 90, 100, 112, 120, 180 or 600 tablets.
750 mg: 14, 20, 28, 30, 50, 56, 60, 84, 90, 100, 112, 120, 180 or 600 tablets.
1000 mg: 14, 20, 28, 30, 50, 56, 60, 84, 90, 100, 112, 120, 180 or 600 tablets.
Not all pack sizes may be marketed.
Marketing Authorisation Holder
Manufacturer1
This leaflet was last revised in October 2025.
1Only actual manufacturer stated on printed leaflet
220 Butterfield, Great Marlings, Luton, LU2 8DL, UK
+44 (0)1480 402 400 [option 2]
+44 (0)1480 402 400 [option 1]
http://www.tillomed.com/
+44 (0)1480 402 400
+44 (0)1480 402 400 [option 1]