Hypoglycaemia is any episode of blood glucose level less than 4 mmol/L, symptomatic or not. It is a common and potentially serious side effect of the treatment of diabetes with a range of oral hypoglycaemic agents and of course with insulin. The commonest therapeutic agents implicated in hypoglycaemia are sulphonylureas and insulin.


Guidelines by NHS Diabetes and the Joint British Diabetes Societies on the management of hypoglycaemia should be read.

 Immediate management

The patient is conscious and cooperative

Administer 20 g of rapidly absorbable carbohydrate, such as 200 ml of orange juice, 100 ml of Lucozade or Coca Cola, five dextrose tablets, or five jelly babies. The BM should be checked 10 minutes later; if still below 4 mmol/L, this recipe should be repeated until it is above 4 mmol/L.

This should then be followed up with 10-15 g of more slowly absorbed carbohydrate such as two biscuits or a slice of bread.

The patient is conscious but uncooperative

In this situation, the first choice should be glucogel administered around the gums, some direct buccal absorption and some ingestion will occur which is usually sufficient to 'rescue' the patient from the worst of the hypo.

After this the guideline for the conscious and cooperative patient can be followed.

However, if the patient is insufficiently cooperative to use this route then management should be as for the unconscious patient.

The patient is unconscious 

If IV access is available, 80 ml of 20% glucose or 160 ml of 10% glucose should be given intravenously over ~10 minutes.

If no IV access is available, and it is not possible to rapidly gain this, then 1 mg of IM glucagon should be given. Once the patient is conscious and the BM is >4 mmol/L, then 15 g of slowly absorbed carbohydrate should be given.

Should the next dose of insulin be omitted?

The next dose of insulin should not be omitted. However if hypoglycaemia is frequent, or recurrent, the doses of insulin should definitely be reviewed.

Is 50% dextrose still used?

Fifty per cent dextrose for IV administration should be avoided as it causes severe injection site discomfort and is a potent venous sclerosant.

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