Dextrose 50% (Glucose 50%)

How it works

It rapidly raises blood glucose by providing a directly usable carbohydrate substrate to the circulation and central nervous system.

Prescribing in practice

• Highly hypertonic and irritant — give into a large or central vein and confirm patency, as extravasation can cause severe tissue necrosis.
• Check capillary or laboratory glucose before and after administration and identify the cause of hypoglycaemia.
• Use cautiously in suspected thiamine deficiency, where thiamine should be considered alongside or before glucose to reduce the risk of precipitating Wernicke's encephalopathy.

Monitoring

Monitor blood glucose closely after administration and recheck regularly until levels are stable.

Counselling the patient

• Explain that this rapidly corrects a dangerously low blood sugar.
• Advise the patient to eat a longer-acting carbohydrate once alert to prevent recurrence.
• Tell the team to watch the cannula site for pain, swelling or leakage.

Evidence & guidelines

Intravenous glucose is the standard parenteral treatment for severe hypoglycaemia in patients unable to take oral carbohydrate.