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Brand Name(s) : Diamicron
Side Effects


Gliclazide should be used with caution in: the elderly, those with mild to moderate liver or kidney disease, pregnancy, people with glucose-6-phosphate-dehydrogenase deficiency, people at risk of hypoglycaemia (e.g. those on a low-calorie diet, malnourished, fasting, skipping meals, eating at irregular intervals, exercising excessively).

It should not be used in: people who have an allergy to gliclazide or any of the other ingredients in the medicine; type 1 diabetes; severe liver or kidney disease; breastfeeding; diabetes complicated by keto-acidosis (ketone bodies and sugar in urine); diabetic pre-coma and coma; diabetics undergoing surgery, after severe trauma or during infections; with medicines to treat fungal infections (miconazole); patients suffering from particular hormone-induced disorders (functional disorders of the thyroid gland, of the pituitary gland or adrenal cortex).

Also see list of precautions and interactions


Keep out of the reach and sight of children.


Gliclazide is used to treat type 2 diabetes mellitus.

It is one of a group of medicines known as sulfonylureas.

It is used to reduce blood sugar levels.

In general this drug is used in the treatment of diabetes mellitus when insulin is not necessary and when diet, exercise and weight loss fail to lower blood glucose (sugar).

Benefits of being on this drug can include control of type 2 diabetes mellitus.

Listed below are the typical uses of gliclazide.

  • Type 2 diabetes mellitus.

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


This medicine is available as standard release tablets and modified release tablets. Modified release tablets liberate the drug over a long period of time and may not need to be taken as often as standard release tablets.

How often do I take it?

  • Take this medication orally usually at breakfast time, with a glass of water. You should always eat a meal after taking your tablet(s). Check the Patient Information Leaflet for instructions on how to use this medicine.
  • Modified release tablets should be swallowed whole with a glass of water and should not be crushed or chewed.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • Drinking alcohol can alter the control of your treatment for diabetes. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately if any of the side effects gets serious.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking gliclazide, tell your doctor or pharmacist if you are allergic to it; or to other sulfonylureas; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: severe hepatic impairment; ketoacidosis; severe trauma; infection, pregnant or breastfeeding.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following: liver or kidney disease, glucose-6-phosphate-dehydrogenase deficiency.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Avoid alcohol or medicines containing alcohol.

The elderly: gliclazide can be used in the elderly.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Gliclazide is not safe to take if you are, or are planning to become, pregnant.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Gliclazide is not safe to take if you are breastfeeding.

Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur: miconazole (a medicine used to treat fungal infections);.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

  • NSAIDs (anti-inflammatory drugs e.g. aspirin)
  • Phenylbutazone (used to treat arthritis)
  • Sulphonamides (used to treat bacterial infections)
  • Coumarin drugs (used to thin the blood)
  • Medicines containing alcohol
  • Fluconazole (used to treat fungal infections)
  • Rifampicin (used in tuberculosis)
  • Sulfinpyrazone (used to treat gout)
  • Monoamine oxidase inhibitors (used to treat depression)
  • Beta blockers (used to treat high blood pressure)
  • Tetracycline compounds (a type of antibiotic)
  • Chloramphenicol (a type of antibiotic),
  • Disopyramide (used to treat irregular heart beat)
  • Miconazole (an oral treatment for fungus infection)
  • Fibrates (used to reduce fat)
  • Cimetidine (used to treat stomach ulcers)
  • Oral contraceptives
  • Steroids
  • Thiazide diuretics (water tablets)
  • Phenothiazine derivatives (a type of sedative),
  • Thyroid hormone

This information does not contain all possible interactions. Therefore, before using glicazide, tell your doctor or pharmacist of all the products you use.


In the event of an overdose, contact your doctor or nearest hospital casualty department immediately.

The symptoms to be expected of overdose are those of hypoglycaemia (low blood suger) - sweating, pale skin colour, hunger pangs, fast heart beat. They can be helped by taking glucose or sweet drinks.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of glicazide or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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