Hypoglycaemia – Low Blood Sugar
Answers to common questions about hypoglycaemia – low blood sugar.
Questions on this page
What is hypoglycaemia?
Hypoglycaemia means blood glucose is too low.
For people with diabetes, a glucose level below 70 mg/dL (3.9 mmol/L) is considered clinically important. A level below 54 mg/dL represents more significant hypoglycaemia.
What causes low blood sugar?
Common causes include:
- Too much insulin
- Certain diabetes tablets
- Delayed or missed meals
- Excessive exercise
- Alcohol
- Reduced food intake during illness
- Changes in kidney or liver function
What are the symptoms?
Symptoms may include:
- Sweating
- Trembling
- Hunger
- Palpitations
- Anxiety
- Irritability
- Dizziness
- Confusion
- Blurred vision
- Drowsiness
Severe hypoglycaemia can cause seizures or loss of consciousness.
What should I do if my sugar is below 70 mg/dL?
If the person is conscious and able to swallow safely, treat with a rapidly absorbed source of glucose or carbohydrate and recheck the glucose after about 15 minutes. Repeat treatment if the glucose remains low.
What if the person is unconscious?
Do not give food or liquid by mouth.
Place the person safely on their side if appropriate, administer glucagon if available and trained to use it, and seek emergency medical help immediately.
What is severe hypoglycaemia?
Severe hypoglycaemia is an event in which the person has altered physical or mental function and requires assistance from another person to recover.
Can hypoglycaemia happen during sleep?
Yes. Night-time hypoglycaemia can occur, particularly in people using insulin or other medicines that can cause low glucose.
Can recurrent hypoglycaemia be dangerous?
Yes. Recurrent episodes can lead to impaired awareness of low glucose and increase the risk of severe episodes.
Can CGM help prevent hypoglycaemia?
Continuous glucose monitoring can be particularly useful in people at high risk of hypoglycaemia and may provide early warning of falling glucose.