Gliclazide

Gliclazide is a type of medicine that can be used to treat people living with type 2 diabetes. 

• What is gliclazide?
• How does gliclazide work?
• How do you take it?
• Who can take gliclazide?
• Your prescription
• Side effects
• Driving and gliclazide
• More information and support

What is gliclazide?

Gliclazide belongs to a group of medicines called sulphonylureas. It is a treatment for type 2 diabetes used to manage blood sugar levels.  

You can take the drug on its own or with other diabetes medications. 

There are many different brands of gliclazide available - some examples are Diamicron, Glydex and Zicron.   

All medication boxes will include the name of the actual drug, so be sure check it also says gliclazide, especially if the box looks different to your usual medication. 

How does gliclazide work?

This drug works by helping your pancreas to make more insulin. It also helps insulin to work more effectively in the body. This all helps to lower blood sugar levels.    

How do you take gliclazide?

It is a tablet that you swallow with a glass of water. It comes in different strengths, and you might take it once or twice a day.  

It comes as standard-release or slow-release tablets. Slow-release tablets mean that the medication is released into the body slowly over time. 

If you take two doses a day, you will normally take one dose with your breakfast and one dose with your evening meal.  

Always take this medication exactly as your healthcare professional has told you. The Patient Information Leaflet inside the box will tell you how to take it but always check with a doctor or pharmacist if you are not sure.  

Who can take gliclazide?

Adults over the age of 18 who have type 2 diabetes can take gliclazide. 

Who can't take gliclazide?

Some medications might not be suitable for some people, which might be because of medical conditions or other reasons:    

• Your doctor will tell you to stop taking gliclazide if you develop diabetic ketoacidosis, or DKA; 
• You might not be able to take gliclazide if you have a condition called acute porphyria; 
• If you have kidney disease you might not be able to take gliclazide, or you might need to reduce your dose, but this will depend on the stage of your kidney disease; 
• If you have severe liver disease you might not be able to take gliclazide; 
• You might need to temporarily stop gliclazide if you’re going to have an operation;  
• You should not take this medication if you are pregnant of breastfeeding. If you’re planning a pregnancy speak with a healthcare professional if you are using this medication.

When you start a new medication always check with your healthcare team that it’s suitable for you to take.   

Your prescription

Your healthcare team should explain your prescription to you but it's important to make sure you ask if you don't feel you know enough.   

And make sure you talk to your GP or your diabetes team if you struggle to take your medication. They might be able to help by giving you a different dose. 

In England, if you need to take any medication to manage your diabetes, your prescriptions will be free. Ask your healthcare team about a prescription exemption certificate if you don't have one, to make sure you don't get charged for your medication. Prescriptions are already free for everybody in the rest of the UK, so you shouldn't pay for your medication.  

Gliclazide can have side effects

Like all medications, gliclazide can cause side effects. But when side effects are listed as common in the Patient Information Leaflet, it doesn’t mean that everyone that takes the medication will get them.   

The information about side effects is based on the likelihood of people having them. For example, if a side effect is very common then it can affect more than one in ten people, and if a side effect is very rare then it affects fewer than one in 10,000 people.  

Because medicines can affect people differently, your healthcare team will speak to you about what’s best for you and discuss any side effects.  

Common side effects are:   

• pain in the tummy 
• feeling sick 
• diarrhoea. 

It's recommended to have a meal straight after taking the tablet to help tackle these side effects. 

Some people find that they gain weight while taking a sulphonylurea. Eating a healthy, balanced diet and physical activity can help you to manage weight gain. 

Risk of low blood sugar

Low blood sugar, also called hypoglycaemia, or a hypo, is a common side effect of taking gliclazide. This is where the level of sugar in your blood drops too low, below 4mmol/l.      

These are not all the side effects. You will find a full list of known side effects in the Patient Information Leaflet. This comes in the medication box.   

It’s also important that you take individual advice from your healthcare team before starting treatment and report any side effects to a healthcare professional, if you experience any.  

You can also report these side effects to the Yellow Card Scheme, which is the government system used for recording side effects with medicines in the UK.   

Driving and gliclazide

This medication can increase the risk of hypos while driving. Speak to your healthcare team if you’re not sure whether you’re at risk of having hypos and what you can do to prevent them.  

More information and support

Still have more questions? Or is there anything you're not sure about after reading this page? Contact our helpline on 0345 123 2399. 

You can visit the NHS website for more information.