Metformin 850mg Tablets
PATIENT LEAFLET: INFORMATION FOR THE USER
METFORMIN 850 mg TABLETS
Read all of this leaflet carefully before you start taking this medicine because it contains important information for you.
- Keep this leaflet. You may need to read it again.
- If you have any further questions, ask your doctor or pharmacist.
- This medicine has been prescribed for you only. Do
not pass it on to others. It may harm them, even if their signs of illness are the same as yours.
- If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. See section 4.
1. What Metformin is and what it is used for
2. What you need to know before you take Metformin
3. How to take Metformin
4. Possible side effects
5. How to store Metformin
6. Contents of the pack and other information
Metformin belongs to a group of medicines called the biguanides. It can be used to treat diabetes.
Insulin is a hormone produced by the pancreas that makes your body take in glucose (sugar) from the blood. Your body uses glucose to produce energy or stores it for future use.
If you have diabetes, your pancreas does not make enough insulin or your body is not able to use properly the insulin it produces. This leads to a high level of glucose in your blood. Metformin helps to lower your blood glucose to as normal a level as possible.
If you are an overweight adult, taking metformin over a long period of time also helps to lower the risk of complications associated with diabetes. Metformin is associated with either a stable body weight or modest weight loss.
Metformin is used to treat patients with type 2 diabetes (also called 'non-insulin dependent diabetes') when diet and exercise alone have not been enough to control your blood sugar levels. It is used particularly in overweight patients.
Adults can take metformin on its own or in combination with other medicines or with insulin to treat diabetes.
If you are not sure why you have been prescribed these tablets then please ask your doctor.
Do not take Metformin
• If you are allergic (hypersensitive) to metformin or any of the other ingredients in the tablets (listed in section 6 of this leaflet)
• If you have recently had a heart attack or treated for acute heart failure, have severe problems with your circulation (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').
• If you have liver or kidney problems (glomerular filtration rate below 45 ml/min)
• If you have uncontrolled diabetes, with e.g. severe hyperglycaemia (high blood glucose), nausea, vomiting, dehydration, rapid weight loss or diabetic 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 unusual fruity odour of the breath.
• If you have recently had a severe infection, such as 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 lost too much water from your body (dehydrated), such as due to long-lasting or severe diarrhoea, or if you have vomited several times in a row. Dehydration may lead to kidney problems, which can put you at risk for lactic acidosis (see 'Warnings and precautions').
• If you drink a lot of alcohol.
If any of the above applies to you, talk to your doctor, before you start taking this medicine.
Tell your doctor before you take this medicine
• If you are going to have an X-ray, which involves having a dye injected. You will need to stop taking metformin at the time of and for a few days after the procedure.
• If you are going to have an operation under general anaesthetic, as you may need to stop taking metformin for a couple of days before and after the operation.
Warnings and precautions
Please note the following particular risk of lactic acidosis.
Metformin may cause a very rare, but very serious complication called lactic acidosis, particularly if your kidneys are not working properly. The risk of developing lactic acidosis is also increased with uncontrolled diabetes, prolonged fasting or alcohol intake, body fluid deficit (dehydration) due to severe diarrhoea or vomiting, liver problems and any medical conditions in which a region of the body is deprived with a lack of oxygen supply (such as acute severe heart diseases).
It is important to you to comply with your medication intake, dietary instructions and regular exercise program because this can reduce the risk of lactic acidosis.
The onset of lactic acidosis can be subtle and the symptoms can be non-specific such as vomiting, bellyache (abdominal pain) 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 seek immediately medical attention as lactic acidosis may lead to coma. Stop taking metformin immediately and contact a doctor or the nearest hospital straight away.
Metformin on its own does not cause hypoglycaemia (a blood glucose level which is too low). However, if you take metformin 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, vision disorders or difficulty in concentration, it usually helps to eat or drink something containing sugar.
Tests while taking Metformin
• The amount of sugar in your blood or urine should be checked regularly.
• At least once a year (more often if you are elderly or have kidney problems) your doctor will check that your kidneys are working properly. Your vitamin B12 levels will also be checked.
Other medicines and Metformin
If you need to have an injection of contrast medicines that contain iodine into your bloodstream, for example for examinations such as X-ray or scan, you must stop taking metformin for a certain period of time before and after (at least 48 hours) the examination (see 'Tell your doctor before you take this medicine' above).
Tell your doctor or pharmacist if you are taking any of the following medicines, as they may affect how metformin tablets work:
• Other medicines for diabetes such as Sulphonylureas or Insulin
• Medicines to increase urine production (diuretics)
• Steroids such as Hydrocortisone or Prednisolone to treat inflammation and allergies
• Beta-2-agonists such as Salbutamol or Terbutaline (used to treat asthma).
Tell your doctor or pharmacist if you are taking or have recently taken, any other medicines, even medicines bought without a prescription.
Metformin with food, drink and alcohol
• You should eat carbohydrates regularly throughout the day.
If your doctor has given you advice on your diet, you should continue to follow this.
• AVOID ALCOHOL when taking Metformin. Alcohol may increase the risk of lactic acidosis especially if you have liver problems or if you are undernourished. This also applies to medicines that contain alcohol.
Pregnancy and breast-feeding
Do not take Metformin if you are pregnant. You need insulin to treat your diabetes. If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.
This medicine is not recommended if you are breast-feeding or if you are planning to breast-feed your baby.
Driving and using machines
Metformin on its own should not affect your ability to drive or operate machinery, but if it is taken with other diabetic medicines you may feel faint, weak, confused and sweaty and you may have fast heart beat, vision disorders or difficulty in concentration. If this happens, do not drive or operate machinery.
Always take Metformin tablets exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure. Metformin cannot replace the benefits of a healthy lifestyle. Continue to follow any advice about diet that your doctor has given you and get some regular exercise.
Swallow each tablet whole with a glass of water. Take with or just after food. This lowers the chance of getting an upset stomach.
Recommended Dose
Your doctor will decide your dose, as it depends on your condition.
DO NOT STOP taking the tablets until your doctor tells you to. Adults:
Typical dose to start with is 500 or 850 mg two or three times a day. The maximum daily dose is 3000 mg taken as 3 divided doses.
In renal impaired patients with a GFR between 45 and 60 ml/min, the starting dose is 500 mg or 850 mg metformin, once daily. The maximum dose is 1000 mg daily, given as 2 divided doses. The renal function should be closely monitored (every 3-6 months).
If you take insulin too, your doctor will tell you how to start metformin.
Elderly:
Your doctor will decide your dose after tests have been carried out on your kidney function.
Children under 10 years: Not recommended.
If you take more Metformin than you should
Contact your doctor or go to a hospital immediately. You may have something called lactic acidosis (see section 4 of this leaflet). The doctor may use a method called haemodialysis to remove the extra lactate and metformin from your body.
If you forget to take Metformin
Don't worry, just take your next scheduled dose at the correct time. Do not take a double dose to make up for a forgotten dose.
If you have any further questions on the use of this product, ask your doctor or pharmacist.
Very rare side effects (in less than 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 such as vomiting, bellyache (abdominal pain) 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 seek immediately medical attention, as lactic acidosis may lead to coma. Stop taking metformin immediately and contact a doctor or the nearest hospital straight away.
• skin rash such as redness of the skin (erythema), itching or an itchy rash (hives).
• low levels of vitamin B12 in the blood. Over time this may lead to anaemia, a sore mouth or tongue or possibly numbness or tingling in the limbs.
• liver problems, abnormal 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 white of the eyes). If this happens to you stop taking metformin and talk to your doctor.
Children and adolescents:
Limited data in children and adolescents showed that adverse events were similar in nature and severity to those reported in adults.
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 directly via Yellow card Scheme, www.mhra.gov.uk/yellowcard. 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 store above 25°C. Store in the original package or container and keep the container tightly closed.
Do not use these tablets after the expiry date, which is stated on the package or container. 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 to protect the environment.
Like all medicines, Metformin can cause side effects, although not everybody gets them. The following side effects may occur:
Very common side effects (in more than 1 in 10 people):
• upset stomach causing nausea (feeling sick), vomiting (being sick), diarrhoea, stomach pain and loss of appetite (anorexia).
These side effects are most likely to happen at the start of the treatment. They usually last for a short time. It helps to take the tablets with or after meals. If symptoms continue, stop taking metformin and talk to your doctor.
Common side effects (in less than 1 in 10 people):
• taste change in your mouth.
What Metformin contains
The active ingredient in Metformin 850 mg tablets is metformin hydrochloride. The other ingredients are sodium starch glycollate, maize starch, povidone, colloidal anhydrous silica, magnesium stearate, hypromellose, titanium dioxide (E171), propylene glycol, macrogol 6000 and purified talc.
What Metformin looks like and contents of the pack
Metformin 850 mg tablets are round white film-coated tablets with the marking MP74 on one side.
The tablets come in blister packs of 28, 30, 50, 56, 60, 84, 100, 250, 300, 308, 350, 500 and 1000 tablets and in containers of 300 and 308 tablets. Not all pack sizes may be marketed.
Marketing Authorisation Holder
Genethics Europe Limited,
41-43 Klimentos, Klimentos Tower,
Nicosia 1061, Cyprus
Manufacturer
DDSA Pharmaceuticals Limited,
310 Old Brompton Road,
London SW5 9JQ
For more information about this product, please contact the Marketing Authorisation Holder.
This leaflet was last revised in 10/2016.
GE0043/O/PIL1/GE2