Diabetes, type 2 - Diagnosis
In this section
If you have diabetes, it's important to get it diagnosed. So if you have been feeling very hungry or thirsty and losing weight for no reason, see your GP.
Sometimes diabetes gives you symptoms early on. Don't ignore them! It's important to diagnose diabetes so that you can start treatment and stay as healthy as possible. For more, see What are the symptoms of type 2 diabetes?
But you might not have any symptoms early on. Sometimes the diagnosis of diabetes starts when your optician tells you to see your GP. This is because diabetes can damage the blood vessels in your eyes. Your optician may pick up this damage during an eye examination.
Your GP will ask you about any symptoms you have, and he or she will probably do a test to see how much glucose (sugar) is in your blood.
Fasting plasma glucose test
Many GPs have small machines called blood glucose meters in their surgery. They can take a drop of your blood by pricking your finger, do the test and give you the result straight away. But these machines aren't as reliable as those in laboratories. You need to have a laboratory test before your doctor can say for sure that you have diabetes.
You should have a test that measures how much glucose is in your blood first thing in the morning, before you have eaten.[1] When you don't eat, it is called fasting. So doctors call this test a fasting plasma glucose test.
The result is your fasting plasma glucose level. If is more than 7 mmol/L, you have diabetes (mmol/L stands for millimoles per litre).
Testing your blood after you've eaten isn't as reliable as testing it when you've been fasting. But you've probably got diabetes if your glucose level is more than 11.1 mmol/L at any time during the day.[1]
For most people, the diagnosis of diabetes is quite easy. But you may need a second test if your glucose level is on the edge of the normal range. That test is called an oral glucose tolerance test.
Oral glucose tolerance test
This is the most reliable test for diagnosing diabetes. It shows how your body copes with a lot of glucose. You may have to go to a hospital clinic to have this test.
You take this test first thing in the morning, before you eat. First, your doctor measures how much glucose is in your blood (your fasting plasma glucose level). Then you drink a very sugary liquid. Two hours later, the level of glucose in your blood is measured again. This is called your two-hour plasma glucose level. If this level is more than 11.1 mmol/L, you have diabetes.
Other tests
If you've just been told you have diabetes, your GP or hospital specialist will probably want to do other tests on your blood and urine. These might include tests to check on your thyroid gland, liver, kidneys and cholesterol.
After you've been diagnosed with diabetes, you should have a thorough check-up once a year with a doctor experienced in treating diabetes.[1] To learn more, see Yearly check-up.
References
- National Institute for Clinical Excellence Diagnosis and management of type 1 diabetes in children, young people and adults. Clinical guideline 15. July 2004. Available at http://www.nice.org.uk/guidance/CG15 (accessed 16 November 2006).
Glossary
- kidney
- Your kidneys are organs that filter your blood to make urine. You have two kidneys, on either side of your body. They are underneath your ribcage, near your back.
- liver
- Your liver is on the right side of your body, just below your ribcage. Your liver does several things in your body, including processing and storing nutrients from food, and breaking down chemicals, such as alcohol.
- cholesterol
- Cholesterol is a fat-like substance made by your liver or absorbed from food. It is used by your body to make bile acids (which help your intestines absorb nutrients) and steroid hormones (like testosterone or oestrogen). Cholesterol is also an important part of cell membranes, which are the structures that surround cells. 'Good cholesterol' is called ; 'bad cholesterol' is .
- thyroid gland
- Your thyroid gland is a small organ that sits in your neck, just in front of your windpipe. It sends out a hormone called thyroxine. This acts on receptors within cells. By acting on the receptors it gives the cells a message to speed up their metabolism and work harder.
© BMJ Publishing Group Limited ("BMJ Group") 2007. All rights reserved
This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
