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Low blood glucose (hypoglycaemia) in type 1 diabetes

Low blood glucose (hypoglycaemia) in type 1 diabetes

Hypoglycaemia (usually called a hypo) means your blood glucose levels are too low (below 4 mmol/litre). This needs to be treated straight away by eating or drinking something with fast‑acting glucose in it (see the box below for examples). If it is not treated quickly, it can make you ill.

Your diabetes team should teach you how to tell when your blood glucose levels are getting low, what to do about it, and how to stop it happening too often.

Younger children can find out more about hypoglycaemia on the Diabetes UK website.

Recognising a hypo

  • The first signs are usually feeling hungry, sweaty and dizzy.

Treating a hypo

  • You can treat it by taking glucose (for example, glucose tablets or a small can of lemonade).

  • You should always have a blood glucose testing kit and some glucose with you, to check if you are getting a hypo and to treat it if you are.

  • Chocolate, biscuits and ice cream are not good at treating hypos, as the glucose in them works too slowly.

  • Your blood glucose levels should start to get better in 15 minutes if you take some glucose. If not, you should take some more glucose.

  • If you cannot treat it yourself (for example, because you're too dizzy or having trouble staying awake), a family member, friend or carer may need to help you.

  • Your diabetes team will tell you what your family, friends or carers can do to help.

Treating a bad (severe) hypo

  • If you are awake but cannot eat or drink easily, you may need to take Glucogel or glucagon.

  • Glucogel is a special gel that you put in your mouth, onto the inside of your cheeks. You can have this instead of other kinds of glucose if you need a quick treatment.

  • You shouldn't have Glucogel or anything else put in your mouth if you're having trouble staying awake because of the hypo, because this could make you choke.

  • If you are having trouble staying awake or have passed out, you may be given a glucagon injection.

  • Your family or carers should know how to give you glucagon injections.

  • Your blood glucose levels should get better after 10 minutes if you have had glucagon. If they do not, your family or carers should call an ambulance.

If you are having trouble staying awake or have passed out

  • If you cannot have Glucogel or other kinds of glucose, and you're not with anybody who knows how to give you a glucagon injection (for example, if you're at school), the people you're with should call an ambulance.

Recovering from a hypo

  • If you have an insulin pump, then after you start to recover from a hypo:

    • You should re‑check your blood glucose and give yourself insulin if you are having a planned snack or meal.

    • You do not need to do anything else if you are not having a planned snack or meal.

  • If you do not have an insulin pump, then after you've started to recover from a hypo, you should either:

    • have a snack or a meal if you have one planned or

    • have a kind of food called 'long‑acting complex carbohydrates' (for example, bread or a cereal bar).

Your diabetes team will tell you if you need to do anything else after you recover from a hypo.

Questions to ask about hypoglycaemia

  • Could you teach me how to tell if I'm getting a hypo?

  • What kind of snack should I have if I'm getting a hypo?

  • How do I use Glucogel?

  • Information Standard