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Hyperglycaemia

When your blood glucose levels are too high, it can cause hyperglycaemia (a hyper).

This can happen if you're:

  • stressed
  • unwell
  • less active
  • not having enough insulin for the carbohydrate you have eaten

Speak to your care team if your blood glucose levels are high and you:

  • feel very thirsty
  • pee more than normal
  • feel tired all the time
  • lose weight without trying
  • have blurred vision
  • have fruity-smelling breath

Very high blood sugar levels can lead to a serious problem called diabetic ketoacidosis (DKA).

Your body starts to break down fat for energy when there's not enough insulin, which leads to a build-up of acid (ketones) in your blood.

It can be life threatening and should be treated in hospital.

Check for ketones if your blood glucose level is higher than 11mmol.

Some meters check for ketones, or you can get strips from your care team to check ketones in your pee.

DKA can develop quickly over a few hours. Infections and drinking too much alcohol are common triggers for DKA.

Speak to your care team immediately if your glucose level is high and you:

  • feel sick or throw up
  • have ketones in your blood or pee
  • have tummy pain
  • are breathing quickly and heavily
  • are dehydrated
  • are struggling to stay awake

You might need treatment in hospital.

Read more about hyperglycaemia on Diabetes UK

Page last reviewed: 7 July 2021
Next review due: 7 July 2024