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Low Blood Sugar Symptoms, Signs & Treatment

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What happens when you are rush to school or work without breakfast? Or at the end of the day when you had been fasting the whole day? Or when you go for a workout unplanned and unprepared? That feeling of weakness and dizziness with may be blurring of vision or crankiness, all points towards low blood sugar levels.

Low blood sugar or glucose means that the blood sugar level is below the required range. It is medically termed hypoglycemia. This may affect any person but most commonly occurs in diabetes. It is a dangerous condition and is considered an emergency in certain cases. It is important to know and realize when the sugar levels are low to be able to prevent and treat it if such a condition occurs.

Why do we need sugar?

All cells of the body use sugar to make energy. They need this energy to run the cellular factories and integral systems. Majority of this sugar is delivered to the cells from the meals that we eat. It comes from carbohydrates, such as rice, potatoes, cereal, fruits, vegetables and sugar itself. Some of the meal sugar is stored in the liver as clumps called glycogen.

An optimal sugar level is usually maintained in the body by the hormones, insulin and glucagon. Insulin works in high blood sugar state or a well-fed state. It pushes the sugar into the cells and by doing this, it reduces the blood level of sugar. Conversely, glucagon works in low sugar and fasting condition where it initiates the breakdown of glycogen, stored glucose, to provide for cellular fuel.

Blood sugar measurements:

The blood glucose level is monitored in two states, fasting and random.

Fasting blood sugar (FBS) is tested after a fasting of 8-12 hours. In normal individuals, FBS should be less than 100mg/dl (5.6mmol/L). A random blood sugar (RBS) is checked randomly during the day, usually recommended two hours after a meal. RBS ranges from 125mg/dl to 180mg/dl (6.9 to10.0 mmol/L).

How low is Low Blood Sugar?

A blood sugar level below 70mg/dL or 3.9mmol/L is hypoglycemia. It requires immediate treatment. If it is not promptly treated or falls below 59mg/dL (3.3mol/L), it becomes life threatening.

Who’s at risk of low sugars?

The most important people that develop hypoglycemia are diabetics. Insulin and sugar-lowering medications are part of their disease management and if not properly taken, result in low sugar states. In addition, if a person has had an episode of hypoglycemia, it is likely that they may develop the condition again. It may involve taking the medication at wrong time, wrong doses, mistakenly repeated dosage, taking medication without food, or not eating enough.

In non-diabetics, or the general population, skipping meal, exercising more than usual, activity without proper diet, big gaps between meals, and drinking too much alcohol results in hypoglycemia.

Certain medications and conditions can also cause hypoglycemia, such as anti-malarial medicine, some antibiotics, kidney failure, anorexia, hepatitis, pancreatic tumor, cancers, and hormonal disorders of adrenals and pituitary. And it may also be seen in children and pregnancy.

Reactive or postprandial hypoglycemia is the condition where the pancreas produces too much insulin in response to normal food intake. This lowers the sugar levels considerably in spite of adequate sugar intake.

Symptoms Signs

Hypoglycemia presents with a wide range of symptoms. Every individual reacts to low sugar levels with varying intensity. Some people develop less symptoms at lower sugars while others may react more to subtle decreases in the sugar level. More or less, the symptoms remain:

  1. Weakness
  2. Shaking/trembling
  3. Dizziness
  4. Sweating
  5. Headache
  6. Intense hunger
  7. Trouble speaking
  8. Uneasiness/nervous
  9. Anxiety
  10. Cranky/irritable
  11. Blurred vision
  12. Clouded thinking
  13. Fast heart beat
  14. Pounding heart


If the sugar level further drops and is not promptly corrected, it may result in:

  1. Fainting
  2. Seizure
  3. Unconsciousness
  4. Coma.

People with uncontrolled diabetes who often develop hypoglycemia, may become unaware of it happening or may only realize it when it is worse.


For low blood sugar, the proverb “prevention is better than cure” fits remarkably well. This is because if the low blood sugar is not cured or treated in time, it damages the whole body and may irreversible damage the brain as well.

In order to prevent such an incident:

For diabetics:

  • A good control of diabetes is much needed, with achievable goals and patient education.
  • Take the advised medications, on instructed time and doses, with proper meals.
  • Discuss with physician to adjust the dose of anti-diabetic medication if needed.
  • Seek help of dietician if dietary requirements are not being fulfilled.
  • For diabetics who have reduced hypoglycemic awareness, continuous glucose monitors and sensors are available.
  • Medical alert bracelets alert the people around the patient to their condition.

For general population:

  • Make sure to have snacks and juices when you exercise.
  • Bedtime snacking for those who develop late night hypoglycemia.
  • Take balanced and well portioned diet on regular intervals with snacks in-between.


Treating hypoglycemia is a two-step pathway. First, correct the hypoglycemia and second, treat the underlying cause. Correcting the blood glucose is only effective for short term and prevents damage; the underlying cause is managed in the long run.

In an episode of low blood glucose, if the patient is awake and able to follow commands, the following management is recommended:

  1. Eat 15gms of carbohydrate, which can be any one of these;
    • 5-6 candies
    • Half a cup of juice or regular soda
    • 1 tablespoon sugar dissolved in a glass of water
    • 1 tablespoon honey or syrup
    • 3 glucose tablets
  2. Wait 15 minutes and recheck blood glucose
  3. If the patient doesn’t feel better or if the sugars are below 70mg/dL, eat another 15gms of sugars from the list above.
  4. Repeat the cycle until sugars are above 70mg/dL or the patient improves.
  5. Take a proper meal after 30 min.

This cycle can be repeated upto 3 times, if the patient does not show signs of improvement, then they should be taken to the emergency department.

If the person is unable to take anything orally, or follow commands, someone else will have to help them and apply honey, jam or Glucogel to the inside of the cheeks and rub it to get it absorbed. It is recommended to get on-call emergency services in the meantime. The person may start to improve in 10-20 minutes.

If the person is not able to take orally or unconscious, lie them on the floor and turn them to their side. A trained person can give them glucagon injection until emergency service arrives. It is important not to put any food in the unconscious person’s mouth as it may block the air passage.


Low blood sugar or hypoglycemia is a dangerous situation and can be life threatening if not promptly treated. It is important to realize the condition and recognize the symptoms to treat it in time. Diabetics are more likely to develop hypoglycemia compared to the general population. Regular meals, proper medications, and good control of diabetes prevents such incidents.

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