Metformin Hydrochloride 1000 mg granules for oral solution – patient leaflet, side effects, dosage

1. What Metformin is and what it is used for

Metformin granules for oral solution contain the active ingredient metformin hydrochloride, a medicine to treat diabetes. It belongs to a group of medicines called biguanides.

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 the insulin it produces properly. 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 glucose levels. It is used particularly in overweight patients.

Adults can take Metformin on its own or together with other medicines to treat diabetes (medicines taken by mouth or insulin).

Children 10 years and over and adolescents can take Metformin on its own or together with insulin.

2. What you need to know before you take Metformin

Do not take Metformin:

• if you are allergic (hypersensitive) to metformin hydrochloride or any of the other ingredients of this medicine (listed in section 6)
• if you have liver problems
• if you have severely reduced kidney function
• if you have uncontrolled diabetes, with for example, severe hyperglycaemia (high blood glucose), feeling sick (nausea), being sick (vomiting), diarrhoea, or rapid weight loss
• if you have symptoms of a condition called lactic acidosis (see “Risk of lactic acidosis” below) or ketoacidosis in which substances called 'ketone bodies' accumulate in the blood and can lead to pre-diabetic 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) 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 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 problems with your circulation (such as shock) or have breathing difficulties. This may lead to a lack in oxygen supply to body tissues 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. Make sure you ask your doctor for advice if:

• you need to have an examination such as an X-ray or a scan involving the injection of contrast medicines that contain iodine into your bloodstream
• you need to have major surgery.

You must stop taking Metformin 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

Metformin may cause a very rare, but 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
• serious infections
• prolonged fasting or alcohol intake
• dehydration due to severe diarrhoea or vomiting (see further information below)
• liver problems
• 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 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 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:

• being sick (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.

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 surgery in which you will be given an anaesthetic (put to sleep), you must stop taking Metformin for a certain period of time before and after the examination or surgery. Your doctor will tell you what you need to do and will decide whether you need any other treatments during this time. Metformin on its own does not cause hypoglycaemia (a condition when your blood glucose levels become 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 heartbeats, vision disorders or difficulty in concentration, it usually helps to eat or drink something containing sugar.

During treatment with Metformin, 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.

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 period of time both before and after the examination. It is important that you discuss this with your doctor beforehand. Tell your doctor or pharmacist if you are taking, have recently taken, or might take any other medicines, including those bought without a prescription.

You may need more frequent blood glucose and kidney function tests or your doctor may adjust the dosage of Metformin. It is especially important to mention the following:

• 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 metformin 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.

Metformin with Alcohol

Avoid excessive alcohol intake while taking metformin 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

Metformin 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 Metformin 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 heartbeat, vision disorders or difficulty in concentration. Do not drive or use machines if you start to feel these symptoms.

Metformin contains aspartame, a source of phenylalanine.

Phenylalanine may be harmful if you have phenylketonuria, a rare genetic disorder in which phenylalanine builds up because the body cannot remove it properly. If this applies to you, Metformin may be harmful for you. Talk to your doctor before you start taking this medicine.

3. How to take Metformin

Always take this medicine 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 take regular exercise.

Recommended dose

Children 10 years and over, and adolescents

• The recommended starting dose is either 500 mg or 850 mg Metformin once a day
• The maximum daily dose is 2000 mg taken as 2 or 3 divided doses

Treatment of children between 10 and 12 years of age is only recommended on specific advice from your doctor, as experience in this age group is limited.

Adults

• The recommended starting dose is either 500 mg or 850 mg Metformin two or three times a day
• The maximum daily dose is 3000 mg taken as 3 divided doses.

If you have reduced kidney function, your doctor may prescribe a lower dose.

If you also take insulin, your doctor will give you advice about how to take this medicine with your insulin. Monitoring

Your doctor will perform regular blood glucose tests and will adapt your dose of Metformin to your blood glucose levels. Make sure that you talk to your doctor regularly. This is particularly important for children and adolescents or if you are an older person.

Your doctor will also check at least once a year how well your kidneys are working. You may need more frequent checks if you are an older person or if your kidneys are not working normally. Directions for use

Take Metformin with or after a meal. This will avoid you having side effects affecting your digestion. Pour the granules into a glass and add 150 ml water to get a clear to slightly cloudy solution. Drink the solution immediately after preparation. If necessary, stir the solution.

If you take one dose a day, take it in the morning (breakfast)

If you take two divided doses a day, take them in the morning (breakfast) and evening (dinner) If you take three divided doses a day, take them in the morning (breakfast), at noon (lunch) and in the evening (dinner).

If, after some time, you think that the effect of Metformin is too strong or too weak, talk to your doctor or pharmacist.

If you take more Metformin than you should

If you have taken more Metformin than you should have, you may experience lactic acidosis (see section 4 ‘Possible side effects’). Symptoms of lactic acidosis are 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 heartbeat. If you experience some of these symptoms, you should seek immediately medical attentions, as lactic acidosis may lead to coma. Stop taking

metformin immediately and contact a doctor or the nearest hosptial straight away. If you forget to take Metformin

Do not take a double dose to make up for a forgotten dose. Take the next dose at the usual time. If you have any further questions on the use of this medicine, ask your doctor or pharmacist.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them. The following side effects may occur.

Metformin can cause a very rare (may effect 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 and contact a doctor of the nearest hospital immediately, as lactic acidosis may lead to coma. Very common side effects (may affect up to 1 in 10 people)

• Digestive problems

Symptoms include:

• feeling sick (nausea)
• being sick (vomiting)
• diarrhoea

• stomach ache (abdominal pain)

  • loss of appetite.

These side effects most often happen at the beginning of the treatment with Metformin. It helps if you spread the doses out over the day and if you take Metformin with or straight after a meal. If symptoms continue, stop taking Metformin and talk to your doctor.

Common side effects (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 side effects (may effect up to 1 in 10,000 people)

• Lactic acidosis

  This is a very rare, but very serious complication particularly if your kidneys are not working properly. Symptoms of lactic acidosis can be non-specific (see ‘warnings and precautions’).

• Liver function

  Abnormalities in liver function tests or hepatitis (inflammation of the liver which may cause:

  • tiredness
  • loss of appetite
  • weight loss
  • possible yellowing of the skin or the whites of the eyes).

If this happens to you, stop taking Metformin 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 side effects 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 the Yellow Card Scheme at: 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 Metformin

Keep this medicine out of the sight and reach of children. If a child is treated with Metformin, parents and caregivers are advised to oversee how this medicine is used.

Do not use Metformin after the expiry date which is stated on the carton or the sachet 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 dispose of medicines you no longer use. These measures will help protect the environment.

6. Contents of the pack and other information

What Metformin granules for oral solution contain

• The active substance is metformin hydrochloride

  • Each sachet of Metformin 500 mg granules for oral solution contains 500 mg metformin hydrochloride corresponding to 390 mg metformin base
  • Each sachet of Metformin 1000 mg granules for oral solution contains 1000 mg metformin hydrochloride corresponding to 780 mg metformin base.
• The other ingredients are aspartame, erythritol, maltodextrin, povidone, anhydrous citric acid, acesulfame potassium, colloidal anhydrous silica, pregelatinized maize starch. What Metformin looks like and contents of the pack

Metformin is white to off-white granules for oral solution, supplied in single-dose sachets. It is available in packs of 20, 30 or 60 single-dose sachets.

Not all pack sizes may be marketed.

Marketing Authorisation Holder and Manufacturer

Marketing Authorisation Holder

Zentiva Pharma UK Limited

12 New Fetter Lane

London

EC4A 1JP

United Kingdom

Manufacturer

Fine Foods & Pharmaceuticals NTM S.p.A.

Via Grignano, 43

24041 - Brembate (BG)

Italy

This leaflet was last revised in March 2025.

1065045559 GENERAL INFO:

1065045559

REASON OF REVISION:

300 × 240 mm

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