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Hypoglycaemia - Hyperglycaemia

Low blood sugar – hypoglycaemia

Hypoglycaemia means low blood glucose. It is sometimes called a "hypo" and it can happen at any time during the day or night. You suffer from hypoglycaemia when your body has insufficient sugar to use as energy, or when your blood glucose level is 3.9 mmol/L and below.

Signs and symptoms of low blood sugar include:

  • Sudden, extreme hunger
  • Headache
  • Blurred vision
  • Trembling
  • Weakness/tiredness
  • Cold sweat
  • Fast heartbeat
  • Anxiety/nervousness
  • Irritability

What to do if you have low blood sugar:

  • Check your blood sugar to confirm that your blood glucose is at a level of 3.9 mmol/L or below.
  • Apply the 15/15 rule:
    • Have 15 grams of a quick-acting carbohydrate, for example: a glass of fruit juice; three to four teaspoons (1 tablespoon) of sugar in water; or five-six hard candies.
      • Or - you can take glucose gel or glucose tablets (see label for 15g amount)
    • Wait 15 minutes and check your blood sugar again.
    • If your blood glucose level is still low, continue to:
      • Alternate 15 grams of glucose with waiting 15 minutes to test your blood glucose until it reaches an acceptable target.
  • Be sure to eat your next meal to prevent another low blood sugar reaction.
  • If symptoms persist, call your doctor.

High blood glucose: hyperglycaemia

High blood glucose can occur when your food, activity and medication are not balanced: too much food, not enough activity and not enough medicine. It can also happen when you are unwell or under stress. If you have high blood glucose levels, you may be more prone to infection. And an infection can cause your blood glucose level to rise even more.

Signs of hyperglycaemia

Hyperglycaemia or high blood glucose is a key indicator of diabetes and therefore, the symptoms are the same as the symptoms of diabetes. These include:

  • Frequent urination
  • Excessive thirst and/or hunger
  • Dry mouth
  • Unexplained weight loss
  • Blurred vision
  • Lack of energy and extreme tiredness

What to do if you have high blood sugar:

  • Call the doctor to see if a change in medication is needed.
  • Check your blood glucose regularly.
  • Drink more water to help remove excess sugar from your blood through urine.
  • Do moderate exercise if your blood glucose is less than 16.7 mmol/L.
  • Refrain from exercise if blood your blood glucose is over 16.7 mmol/L and ketones are found in your urine.
  • Reduce food portions in succeeding meals.

Recording your blood glucose results:

  • Keep a log book handy, where you can manually record your blood glucose readings.
  • You can find log books at your doctor’s office, health care centers, and even online.
  • Always update your log book and take it with you to your doctor visits so that he and your health care team will have a clearer understanding of your blood glucose profile, which will help them in prescribing the proper treatment plan.

2American Diabetes Association. (ADA) Glycemic Targets Sec. - In Standards of Medical Care in Diabetes - 2016. Diabetes Care 2016; 39 (Suppl. 1): S43.
3A1c/eAG – ADA Diabetes Advisor series – accessed April 4, 2016.