Hypoglycaemia is the medical term for low blood glucose levels. This occurs when people taking tablets or insulin for their diabetes have a blood glucose level below approx 4 mmol/L.

What is hypoglycaemia?

Hypoglycaemia (commonly know as a ‘Hypo’) means low blood glucose. If left untreated it can result in a loss of consciousness, or in severe cases, coma. This can occur if you take medication for diabetes¹.

What causes hypoglycaemia?

People who take insulin or certain diabetes oral medications are likely to experience hypoglycaemia¹. Any one of the following, or a combination, may cause low blood glucose².

• Skipping or delaying a meal
• Not eating enough carbohydrate
• A long interval between giving insulin and a meal
• Excessive exercise or exercising for a long time without eating
• Medication
• Taking too much insulin or diabetes medication
• Changing the time that you take your insulin or diabetes medication

What are the warning signs of hypoglycaemia?

Each individual’s experience is unique. However, the following are the most common signs and symptoms for hypoglycaemia:

• Inability to think straight/confusion
• Shakiness
• Sweatiness
• Clammy skin
• Anxiety/nervousness
• Blurred vision
• Hunger
• Irritability or moodiness
• Numb lips and tongue
• Difficulty in speaking
• Headache
• Rapid heart beat
• Weak knees
• Fainting/unconsciousness

Special precautions

You can experience the symptoms or warning signs of hypoglycaemia even if your blood glucose is not too low.

This can occur when:

• Your blood glucose drops very quickly
• You are very anxious

It is possible to experience hypoglycaemia without first experiencing the warning signs. This is why self-monitoring is essential for good diabetes management. Tests should be performed routinely, as advised by your healthcare team. Extra testing should also be performed when you exercise, when you are ill, or stressed¹.

What to do if you experience hypoglycaemia?

Always correct low blood glucose levels immediately.

Firstly, make sure you’re safe. (eg. If your driving, pull over to the side of the road.)

In the absence of specific advice from your healthcare professional, the follow steps are recommended²:

Step 1. Have some quick acting carbohydrate that is easy to consume, for example:

• Half a can of regular soft drink (not ‘diet’) or
• Half a glass of fruit juice or
• 3 teaspoons of sugar or honey or
• 6-7 jellybeans or
• Glucose tablets equivalent to 15 grams of carbohydrate

Step 2. Wait 10 – 15 minutes. Check your glucose levels again. If your blood glucose isn’t rising, repeat treatment with a quick acting carbohydrate as described above.

Step 3. If you don’t expect to have a meal within 20 minutes after you experience low blood glucose, you will need to have some longer acting carbohydrate such as a sandwich, or a glass of milk, or a piece of fruit, or 6 small dry biscuits and cheese or a tub of natural low fat yoghurt.

You should call a member of your healthcare team if you:

• Are new to diabetes medication or think your medication may need to be changed
• Have three or four low blood glucose events in a row
• Experience a severe hypoglycaemic event (ie lose consciousness)
• Experience low blood glucose the same time every day for several days in a row
• Have needed someone to help you due to the severity of the low blood glucose event

Reference:
1. Standards of Medical Care in Diabetes, American Diabetes Association, 2008: Diabetes Care, 31:512.
2. Diabetes Australia website http://www.diabetesaustralia.com.au