Testing your blood sugar levels is a vital part of managing diabetes, so find out about tests, like the finger-prick and HbA1c, and when to use each.

When you need to have a finger-prick test

This test lets you check your blood sugar levels on a regular basis when you need to, either at home or when you’re out.

The test tells you if your blood sugar levels are too low, too high or normal, and it is done by:

  • everyone with type 1 diabetes
  • everyone with gestational diabetes
  • pregnant women with type 1 and type 2 diabetes
  • some people with type 2 diabetes who are taking insulin or tablets called sulphonylureas for diabetes (your GP should tell you)

The test strip from the finger prick is put into a machine called a “glucometer”, which reads and displays your sugar level on a screen.

When you need to have a HbA1c blood test

HbA1c is a blood test that checks if sugar levels have been too high, on target or returned to normal over the past three months. It measures the amount of blood sugar which has stuck to the protein in your red blood cells which carries oxygen around the body haemoglobin (Hb).

Because red blood cells last three months on average, HbA1c gives clinical teams good information about the average blood sugar level over the three- month period.

HbA1c should be done at least once a year, but especially if it's too high, you will need to have this test done at three or six month intervals.

This type of test is done at your GP’s or your hospital’s diabetes services.

What is continuous glucose monitoring (CGM)?

Continuous glucose monitors use a sensor to detect glucose and show it on a receiver or mobile phone. They also provide alarms for when glucose levels are falling or rising quickly, or if glucose is high or low.

People on insulin pump therapy or frequent insulin injections can benefit from continuous glucose monitors. You can buy continuous glucose monitors online or they may be funded on the NHS if you have type 1 diabetes. However there is guidance of who is eligible and you can discuss this with your doctor or nurse specialist.

Flash Glucose Monitoring (FreeStyle Libre)

Flash monitoring can replace blood glucose checking and uses a similar sensor to continuous glucose monitoring. Although flash monitoring doesn’t give you alarms, it can show the last few hours of glucose values and whether the glucose is going up or down.

You can buy this devices online and some patients will be able to get funding on the NHS if they are eligible, you can discuss this with your doctor or nurse specialist.