HealthInfo Canterbury

Low blood sugar (hypoglycaemia)

Hypoglycaemia, also called a hypo, means you have a low blood sugar (glucose) level. Anything less than 4 is low. It happens mainly if you inject insulin, but it can also happen with some tablets.

• If your blood sugar is between 3.5 and 4, and you feel OK, have a meal if it is due soon, or a snack.
• If your blood sugar is below 3.5, have ONE of the following options:
  • one Hypo-Fit sachet, OR
  • three to four glucose tablets, OR
  • five jelly beans, OR
  • half a glass of ordinary (non-diet) soft drink, OR
  • one tablespoon of jam or sugar, OR
  • half a glass of fruit juice, OR
  • one tablespoon of glucose, dissolved in water.

Wait 10 minutes, then test your blood sugar again.

• If your blood sugar is still below 3.5, have a repeat helping from the list above.
• Once your blood sugar is above 3.5, have a meal if it is due, or a snack such as:
  • a sandwich made with one piece of bread, OR
  • a piece of fruit such as half a banana, OR
  • a glass of milk.

What causes a hypo?

You can have a hypo if you:

• miss or delay a meal
• don't have enough starchy food (carbohydrates) with your meal or snack
• do extra exercise or physical work, and don't have extra food to fuel it
• have too much insulin, or take too many diabetes tablets
• drink too much alcohol, or drink alcohol on an empty stomach
• allow too much time between your injection and your meal
• change the time that you have your insulin or tablets.

What are the warning signs of a hypo?

If you are having a hypo, you are like to have some of the following symptoms:

• pins and needles in your mouth and tongue
• sweating
• pale skin
• shaking hands or legs
• a headache
• blurred vision
• a fluttering heart (palpitations).

You may also feel:

• dizzy
• nervous
• sleepy
• hungry
• confused
• unable to concentrate.

What else should I know about hypos?

You can have a hypo without having any symptoms. This can happen if you haven't eaten for a long time, have given yourself too much insulin, or exercised hard without having any extra food. If you think there's a danger you might be having a hypo, even without symptoms, test your blood sugar level.

You should always carry a hypo treatment with you. If you don't treat a hypo, you may lose consciousness, or have a fit or seizure.

If you have a hypo before a meal, you should follow the instructions above to get your blood sugar level above 3.5. Then, have insulin either just before your meal (Penmix) or straight after it (Apidra, Humalog, Humalog Mix 25, Humalog Mix 50, NovoMix 30 or NovoRapid).

You might have symptoms of a hypo when your blood sugar level is not low if:

• your blood sugar level is regularly high, and it drops quickly to normal
• you are anxious.

You risk losing your licence if you drive when you are having a hypo. Tell your doctor or diabetes nurse if you keep having hypos.

On the next page: Guidelines for giving glucagon

Written by Christchurch Diabetes Centre. Adapted by HealthInfo clinical advisers. Endorsed by clinical director, Diabetes Services, Canterbury DHB. Last reviewed May 2016.

Source

Jelly beans image courtesy of Bill Longshaw at FreeDigitalPhotos.net

Page reference: 178645

Review key: HIDIA-21832