If it is not possible to control the sugar level in your blood by following healthy eating recommendations, your doctor may prescribe a diabetes tablets. This does not mean your diabetes is more severe, just that you need some extra help to control your blood sugar levels. Diabetes tablets are not for insulin. You will still need to follow the eating guidelines you have been given. There are three types of diabetes tablets and they work in different ways to lower your blood sugar levels.

The 3 groups are called

Most medicines have at least two names. One is the proper (generic) name which is usually used by doctors and nurses, and the other is the brand name given to it by the manufacturer. If you are ever unsure that you have the correct tablets from the pharmacy, do ask the pharmacist.


This type of tablets is usually used for people who are of normal weight or underweight, as it may encourage weight gain. It stimulates your pancreas to produce more insulin which will then lower your blood sugar. The sulphonylureas include chloropropamide, glibenclamide, gliclazide, glipizide, gliquidone, tolazamide and tolbutamide.

Sulphonylureas may cause mild indigestion, headache, skin rashes and weight gain. Some sulphonylureas may make your face flush if you drink alcohol. If any of these side effects happen to you, please discuss it with your diabetes care team or GP. Sulphonylureas may also cause low blood sugars (hypoglycaemia). Please ask your diabetes care team about how to prevent and treat low blood sugars.


The only tablet in this group is metformin. It works by helping your insulin to use the sugar in your body more effectively. It is usually used for people with diabetes who are overweight because it does not encourage weight gain. Some people (but not everyone), may find that starting metformin causes stomach upsets such as nausea, vomiting, diarrhoea, indigestion and loss of appetite. These can be helped by taking metformin with or after food. If these problems keep happening to you, discuss with your diabetes team or GP. Metformin does not cause low blood sugars (hypos).

Alpha glucosidase inhibitors

The only tablet in this group is acarbose. It works by delaying the rate at which you digest sugars which in turn slows down the rate at which your blood sugar rises, after you have eaten. Acarbose sometimes causes wind, a rumbling stomach, a feeling of fullness, diarrhoea or soft, smelly stools. Again, if these symptoms do not settle down, talk to your diabetes team. Acarbose used by itself does not cause low blood sugars (hypos).

What do I do if I forget to take my diabetes tablet?

If you remember your tablet only an hour or two later, take it then. If it is longer, miss that dose and take your next tablet at the usual time. DO NOT EVER double your dose because you have missed a tablet.

What happens if I am ill?

DO NOT stop taking your tablets. If you are vomiting and can't keep your tablets down and if your urine or blood sugars are high, contact your diabetes care team straight away.

Will other medication affect my diabetes tablets?

Will I have to pay for my prescriptions?

If you need to take tablets for your diabetes, you are entitled to life-long free prescriptions for these tablets and any other medication you need. Ask your doctor or nurse for form P11.

What happens if one type of tablet does not work?

You may find that your tablet requirements change over the course of your diabetes. It is very important to have regular checks with your diabetes care team to ensure your treatment is still right for you. Some people take a combination of tablets to control their blood sugar levels. Sometimes this is not enough and a mix of tablets and insulin will be needed. If insulin alone is necessary you will receive a lot of support from your diabetes care team to help you adjust to the change.