Good diabetes management involves controlling blood glucose. Studies have shown that keeping blood glucose levels close to normal helps prevent long-term complications. However, it can also increase the risk of having low blood glucose. It is essential to recognize and treat symptoms quickly. Quick treatment can prevent severe effects.

What is low blood glucose?

Low blood glucose occurs when the glucose level in the blood falls below 4.0 mmol/L. Below this level the body is not supplied with the energy it needs.

What are the symptoms of low blood glucose?

Someone with low blood glucose may feel tired, dizzy, confused, anxious, hungry or weak. Sweating, trembling, rapid heartbeat, and tingling or numb lips are also signs. Not all people have exactly the same symptoms.

Why does low blood glucose develop?

Changes in everyday activities are the most common cause of low blood glucose. These changes may include:

taking too much medication
missing or delaying meals or snacks
eating too little food
increasing physical activity.

Can anyone with diabetes experience low blood glucose?

If you take one or more of the following medications to treat your diabetes, it is possible for your blood glucose to fall below 4.0 mmol/L.

insulin
glyburide (Diabeta®)
gliclazide (Diamicron®)
glimepiride (Amaryl®)
tolbutamide
chlorpropamide
nateglinide (Starlix®)
repaglinide (GlucoNorm®).

It is unlikely that you will experience low blood glucose symptoms if you manage your diabetes through diet and physical activity alone, or use only these medications:

metformin (Glucophage® or Glumetza®)
acarbose (Glucobay®)
rosiglitazone (Avandia®)
pioglitazone (Actos®)
Avandamet®
sitagliptin (Januvia®)
saxagliptin (Onglyza®)
linagliptin (Tradjenta®)
Janumet®
liraglutide (Victoza®)
exenatide (Byetta®).

Treating low blood glucose

STEP
1If you have symptoms, check your blood glucose. If it is less than 4 mmol/L, your blood glucose is too low. If it is not possible to check, treat your symptoms as if you have low blood glucose.

STEP
2Eat or drink 15 grams of fast-acting carbohydrate, such as one of the following:

5 Dextrosol® or 4 Dex4® tablets
¾ cup (175 mL) juice or regular soft drink
3 teaspoons (15 mL) of sugar dissolved in water
6 Life Savers®
3 teaspoons (15 mL) of honey.

If you are taking acarbose (Glucobay®), you must use glucose tablets or 1-¼ cups of skim milk to raise your blood glucose level. Acarbose slows down the absorption of other fast-acting carbohydrates.

Glucose (also known as dextrose) tablets work faster than other types of treatment to raise the blood glucose level. Keep these tablets readily available at home, at work, and with you at all times.

Tell family, friends, and co-workers what symptoms to watch for and how to help. Let them know that low blood glucose may make you act as if you were drunk.

When treating low blood glucose, remember to eat or drink only the 15 grams of fast-acting carbohydrate until your blood glucose rises above 4.0 mmol/L. Low blood glucose can cause anxiety that may make you feel like you need to eat more right away. However, if you eat too much, your blood glucose may become very high.

Check with your diabetes educator for the recommended amount of fast-acting carbohydrate to use in treating children.

STEP
3 Recheck your blood glucose after 15 minutes. If it is still below 4.0 mmol/L, treat again with another 15 grams of fast-acting carbohydrate.

STEP
4 Once your blood glucose level is above 4.0 mmol/L, have your normal meal or snack. If your next meal is more than an hour away, make sure your snack includes 15 grams of carbohydrate and a protein source. For instance, choose six crackers with peanut butter or cheese, or half of a meat, peanut butter or cheese sandwich. This should prevent low blood glucose before your next meal or snack.

How can I prevent low blood glucose?

Learn how medication, food, and physical activity affect your blood glucose levels. Regular blood glucose checks can help you keep it under control. Staying aware of your blood glucose level allows you to adjust food intake and physical activity to avoid low blood glucose.
Eat regular meals and snacks. Eat enough at each meal and try not to skip or delay eating. Talk to your doctor, dietitian, or diabetes educator about what to eat on days when you are feeling sick. You must continue eating and drinking foods containing carbohydrate to prevent low blood glucose during sick days.
If you are more physically active than usual, check your blood glucose more often and eat more food as needed.
Have a fast-acting carbohydrate with you at all times. Glucose tablets are inexpensive and easy to carry. Pick up a few packages from your pharmacy and replace your supply as you use them.

What if I need emergency help from others?

Know the symptoms of low blood glucose and how to treat it. Tell family, friends, and coworkers what to watch for and how to help. Let them know that low blood glucose may make you act as if you were drunk. Low blood glucose can also cause confusion that makes it difficult for you to treat yourself. Quick treatment can prevent mild low blood glucose from becoming more serious.

Noticing and treating symptoms of low blood glucose immediately prevents blood glucose levels from dropping to a level that can cause unconsciousness or seizures. You need emergency assistance immediately if you are unable to swallow or unconscious. First, 911 or emergency assistance should be called. Glucagon, a hormone, can be given by injection to quickly raise the blood glucose level of an unconscious person. Only someone who has been trained to inject glucagon should do so.

Knowing about low blood glucose helps to prevent it. Notice and quickly treat low blood glucose to stop it from becoming more serious. This keeps you safe as you try to achieve good diabetes control. Melanie knew what to do when her husband Norm showed symptoms. Now, you do too!

Dealing with Low Blood Glucose Quick recognition and treatment is essential