What is a low blood sugar (hypoglycemia) emergency?
Low blood sugar (hypoglycemia) means that the level of sugar
(glucose) in your blood has dropped below what your body needs to function
normally. When your blood sugar level drops below 3.6 millimoles per litre (mmol/L), you most likely will have symptoms, such as feeling tired, weak, or
shaky.
Symptoms of low blood sugar can develop
quickly.
- If your blood sugar level drops just slightly
below a safe range, you may have symptoms of mild low blood sugar. If you eat
something that contains sugar, these symptoms may last only a short time. If
you have had diabetes for many years, you may not always notice symptoms of
mild low blood sugar. This is called
hypoglycemia unawareness.
- If your blood
sugar level continues to drop (usually below 2.2 mmol/L), your behaviour may
change. Symptoms of moderate low blood sugar may develop. You may become too
weak or confused to eat something to raise your blood sugar
level.
- If your blood sugar level drops very low (usually below 1.1 mmol/L), you may lose consciousness or have a seizure. If you have symptoms of
severe low blood sugar, you need medical care immediately.
Sometimes people with diabetes have low blood sugar levels during
the night. If your blood sugar level drops during the night, you may wake up in
a cold sweat and feel weak, or you may sleep through it. Your body may use
stored sugar to raise your blood sugar level back toward a safe range. If this
happens, you most likely will wake up in the morning with a headache and
possibly high blood sugar.
What causes low blood sugar?
Low blood sugar (hypoglycemia) can develop rapidly (within 10 to 15
minutes). It can occur if you:
- Take too much insulin.
- Skip or
delay a meal or snack.
- Exercise too much without eating enough
food.
- Drink too much alcohol, especially on an empty
stomach.
- Take certain
medications that lower blood sugar. Some medications
that you can buy without a prescription can affect blood sugar levels. Talk
with your health professional about your prescription and non-prescription
medications and whether they may increase your risk of developing very low
blood sugar levels.
- Start your menstrual period. The hormonal
changes may affect how insulin works.
You may have symptoms of low blood sugar if your blood sugar drops
from a high level to a lower level. For example, if your blood sugar level has
been higher than 16.6 mmol/L for a week or so and the level drops suddenly to 5.6 mmol/L, you may have symptoms of low blood sugar. However, if you have had
diabetes for many years, you may not have symptoms of low blood sugar until
your blood sugar level is very low.
Test Your Knowledge
Determine whether the following statements are true.
Low blood sugar means that the level of sugar in the
blood has dropped below what the body needs to function normally (usually below
3.6 mmol/L).
- True
- False
A very low blood sugar level (below 1.1 mmol/L) is an
emergency that requires immediate care.
- True
- False
Continue to
Why do I need to deal with low blood sugar emergencies?
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Dealing with low blood sugar from insulin for diabetes