Metformin Hydrochloride RxFarma 500mg Prolonged-release Tablets

• Keep this leaflet. You may need to read it again.
• If you have any further questions, please ask your doctor, pharmacist or nurse.
• 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, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. See section 4.

1. What Metformin PR tablets are and what they are used for
2. What you need to know before you take Metformin PR tablets
3. How to take Metformin PR tablets
4. Possible side effects
5. How to store Metformin PR tablets
6. Contents of the pack and other information

• If you are allergic to to metformin hydrochloride or to any of the other ingredients of this medicine (listed in section 6). An allergic reaction may cause a rash, itching or shortness of breath.
• if you have uncontrolled diabetes, with, for example, severe hyperglycaemia (high blood glucose), 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 have severely reduced kidney function.
• if you have lost too much water from your body (dehydration). Dehydration may lead to kidney problems, which can put you at risk for lactic acidosis (see 'Warnings and precautions').
• if you have liver problems
• if you have been treated for acute heart problems or have recently had a heart attack or have severe circulatory problems or 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 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 a heavy drinker of alcohol.
• if you are under 18 years of age.

Risk of lactic acidosis

Metformin PR 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 Metformin PR 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 PR 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:

• stomach-ache (abdominal pain)
• muscle cramps
• vomiting
• 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

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.

If you need to have major surgery, you must stop taking Metformin PR during and for some time after the procedure. Your doctor will decide when you must stop and when to restart your treatment with Metformin PR.

During treatment with Metformin PR, 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 prolonged-release tablet 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 PR before or at the time of injection. Your doctor will decide when you must stop and when to restart your treatment with Metformin PR.

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 PR. It is especially important to mention the following:

• 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)
• Medicines which increase urine production (diuretics (water tablets) such as furosemide).
• Steroids such as prednisolone, mometasone, beclometasone.
• Sympathomimetic medicines including epinephrine and dopamine used to treat heart attacks and low blood pressure. Epinephrine is also included in some dental anaesthetics.
• Medicines that may change the amount of Metformin PR in your blood, especially if you have reduced kidney function (such as verapamil, rifampicin, cimetidine, dolutegravir, ranolazine, trimethoprim, vandetanib, isavuconazole, crizotinib, olaparib).

Avoid excessive alcohol intake while taking Metformin PR tablets 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 glucase levels.

This medicine is not recommended if you are breast-feeding or if you are planning to breast-feed your baby.

Metformin PR 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 PR.

Metformin PR tablets 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 PR taken with other antidiabetic medicines can cause hypos, so in this case you should take extra care when driving or operating machinery.

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 heartbeat.

If you experience some of these symptoms, you should immediately seek medical attention, as lactic acidosis may lead to coma. Stop taking Metformin PR 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 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 at: www.mhra.gov.uk/yellowcard.

By reporting side effects you can help provide more information on the safety of this medicine.

500mg: Each prolonged-release tablet contains 500 mg metformin hydrochloride corresponding to 390 mg metformin base.

750mg: Each prolonged-release tablet contains 750 mg metformin hydrochloride corresponding to 585 mg metformin base.

1000mg: Each prolonged-release tablet contains 1000mg metformin hydrochloride corresponding to 780 mg metformin base

The other ingredients are:

Hypromellose

Povidone

Colloidal Anhydrous silica

Magnesium Stearate

Opadry (OY-7300) containing Hypromellose, titanium dioxide, macrogol 400/PEG.

500mg: White, oval shaped, 18.1 mm x 10 mm film-coated tablets, debossed “MT” on one side and “500” on other side.

750mg: White, oval shaped, 19.1 mm x 10.6 mm film-coated tablets, debossed “MT” on one side and “750” on other side.

1000mg: White, oval shaped, 20.2 mm x 11.4 mm film-coated tablets, debossed “MT” on one side and “1000” on other side.

Metformin PR tablets are available in Alu-PVC/PVDC Blister packs of 28, 30, 50, 56, 60, 84, 90, 100 and 112 tablets.

Not all pack sizes may be marketed.

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