Low Blood Sugar

Definition and Symptoms

Low blood sugar (hypoglycemia) is the most common and most dangerous condition for many people with type 1 diabetes (T1D). Very low blood sugar may lead to insulin shock, which can be life threatening if not promptly treated. Low blood sugar occurs when the body has too little food/glucose or too much insulin.

The following are all potential reasons that a person with diabetes might have low blood sugar:

  • Too much insulin taken
  • Eating less than usual
  • Eating later than usual
  • Insulin was injected at a site on the body where the absorption rate is faster than usual
  • Injecting extra insulin after forgetting about a previous dose
  • More exercise than normal
  • Illness or injury
  • Other hormones
  • Medication interaction

The following is a list of general symptoms that indicate low blood sugar (the person with type 1 diabetes may exhibit one or more of these):

  • Dizziness
  • Nervousness
  • Personality change/irrational behavior
  • Blurry vision
  • Shakiness
  • Nausea
  • Crying
  • Sluggishness
  • Sweating
  • Poor coordination
  • Hunger
  • Lightheadedness
  • Irritability
  • Drowsiness
  • Erratic response to questions
  • Inability to concentrate

Severe symptoms (symptoms as listed above, plus):

  • Convulsions
  • Unconsciousness

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What to Do About Low Blood Sugar Levels

A blood glucose meter reading below the target range specified by the physician indicates low blood sugar. The following are general treatments for low blood sugar. The physician and parents (for a child) should determine what course to follow. Please note that people with type 1 diabetes (T1D) have symptoms of low blood sugar at various readings. Some people with T1D feel perfectly fine at readings below 70. Others begin to show low blood sugar symptoms at readings somewhat above 70.

1. If blood sugar levels are slightly low and the person is alert and lucid, he or she should:

  • Not exercise.
  • Eat. After eating, check blood sugar level again to make sure it is within the target range. The person may require another snack later in the day.
  • Continue to check blood sugar levels regularly.

2. If blood sugar levels are low and the individual is showing signs of low blood sugar but is still able to eat:

  • He or she should immediately eat or drink a fast-acting source of glucose (i.e., juice, glucose gel, or tablets). He or she may need to eat more food after that (i.e., crackers or other complex carbohydrate).
  • Continue to check blood sugar levels regularly.

3. If blood sugar levels are low and the individual is showing signs of low blood sugar and is unconscious, convulsing, and/or unable to swallow:

  • Remain calm.
  • DO NOT administer food or drink to an unconscious person, as it may obstruct the airway.
  • Position the individual on the floor on his/her side to prevent falling, injury, or choking.
  • Call 911.
  • Administer emergency glucagon shot (unconsciousness may last up to 10 minutes post-glucagon; be prepared for vomiting as the individual becomes conscious).
  • Continue to check blood sugar levels regularly.
  • Give additional food (i.e., crackers or other complex carbohydrate) when able to eat, if needed, in order to keep blood sugar levels in target range.

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