A guide to testing for people with diabetes

Types of test

Urine tests

Glucose spills over into the urine when your blood glucose level is too high. When your kidneys filter your blood, any excess glucose is passed into your urine. So urine tests can show how well controlled your diabetes has been over the previous few hours. It is not normal to have glucose in the urine and a negative urine test usually indicates good diabetic control.

Blood glucose testing at home

The level of glucose in your blood is changing all the time. Testing your blood will tell you what your level of blood glucose is at that moment. Glucose levels may be changed by food, exercise, medication and illness. Test results may help you work out patterns in your day-to-day glucose levels. Make a record of your results to discuss with your doctor. Your blood glucose level should be between 4 and 6mmol/l before meals and less than 10mmol/l two hours after food.

There are many meters and finger-pricking devices on the market. Ask advice from your surgery or diabetes clinic before you buy one . Never share or borrow a finger-pricking device.

Blood glucose testing at the surgery

This measures a substance in the blood called HbA 1c (also called Haemoglobin A 1c or Glycated Haemoglobin) which gives an accurate measure of your level of diabetic control over the past few weeks. It should be checked at least every six months. If you have had high levels of glucose in your blood during the previous few weeks your HbA 1c will be high.

Your HbA 1c should be between 6.5 and 7.5. Your doctor or nurse will help you adjust your diet and medication to reach your individual target. It may be difficult to achieve normal levels all the time and if your HbA 1c is high, any improvement will help reduce the risk of associated health problems.

When and how often to test

Discuss this with your diabetes nurse, practice nurse or doctor. They will help you choose which type of testing will help you and the best times to test. For blood glucose testing, test at different times of the day rather than at a single fixed time.

Testing varies depending on whether you need insulin or tablets to control your diabetes.

People with type 1 diabetes and type 2 diabetes using insulin

On certain types of insulin and if your diabetes is well-controlled, a daily test, at varying times, may be sufficient. If you are using blood testing to adjust your lifestyle or medication you may benefit from testing up to four times a day.

People with type 2 diabetes taking certain tablets where there is a risk of hypoglycaemia ("hypos" or very low blood glucose levels)

If you are taking gliclazide (Diamicron ® , Diamicron MR ® ); glibenclamide (Daonil ® , Semi-Daonil ® , Euglucon ® ); glimepiride (Amaryl ® ); glipizide (Glibenese ® , Minodiab ® ), tolbutamide or chlorpropamide b lood glucose testing should help you identify if there is a risk of too low blood sugar levels. Testing 3 times a week is recommended.

People with type 2 diabetes on diet alone or taking metformin (Glucophage ® ) or pioglitazone (Actos ® ) or rosiglitazone (Avandia)

There no need to test your blood glucose levels routinely but only in the circumstances described in the box below.

For all people with diabetes, extra tests should be performed at times such as :

Illness or stress
Changes in insulin or oral medication
Treatment with steroids
Pregnancy or if a pregnancy is considered or possible

People who are taking medication that puts them at risk of low glucose levels (hypoglycaemia) should also test:

Before driving and at regular intervals during a journey
When glucose levels vary a great deal
When the level of activity changes e.g. during and after exercise or sport, on holiday

Record keeping.

Keep a record of your readings and the date they were made. This can help you recognise regular patterns. Take your results with you to your clinic appointments so that you can discuss them with your doctor or nurse.

Only test if you need to

Only order the amount of test strips you need - your surgery offers a repeat prescription service in 48 hours .

North, East, Mid Devon and Exeter Diabetes monitoring guidelines for people with diabetes . May 2004.