What is hypoglycemia and what are it's symptoms?

Though in general population hypoglycemia is uncommon, in diabetic patients especially who are being treated with insulin may have frequent attacks of hypoglycemia. So what is exactly hypoglycemia?

According to the Davidson's principles and practice of medicine, in a diabetic patient when the level of blood sugar fall below 3.9 mmol/L (70 mg /dl) it is called hypoglycemia. If any time, in non-diabetic person, blood sugar fall below the mentioned level it is called spontaneous hypoglycemia.

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Before going to learn about the symptoms of hypoglycemia we need to know a few facts.

The function of insulin is to keep blood sugar under control by pushing sugar out of blood into Liver, muscle and fat cells. In normal individuals, when sugar is less in blood, insulin is not secreted from beta cells of the pancreas. So sugar doesn't fall too much to create symptoms. But when a diabetic patient take insulin subcutaneously, it keeps working despite of the low sugar in blood, hence hypoglycemia takes place.

Unlike other tissues in the body, our Brain completely depends on blood sugar for the energy. Sugar is the only fuel for brain, neither fatty acid nor protein. So when blood sugar falls below normal limit, brain is affected very fast.

Now, what are the symptoms of hypoglycemia?

Symptoms can be categorised into two groups:

• Those due to activation of autonomic nervous system &
• Those due to deprivation of sugar in brain (neuroglycopenia)

Autonomic symptoms:

• Sweating
• Trembling
• Pounding heart
• Hunger
• Anxiety

Symptoms due to deprivation of sugar in brain:

• Delirium or acute confusional state
• Drowsiness
• Speech difficulties
• Inability to concentrate
• Incoordination
• Irritability and anger
• Visual disturbance
• Ataxia

A few non-specific symptoms:

• Nausea
• Headache
• Tiredness

Special note:

Symptoms might differ according to the age of the patient. Children usually show behaviour change e.g naughtiness or irritability. On the other hand, older people show neurological symptoms e.g visual disturbance or ataxia