Hypoglycemia And Headaches

Hypoglycemia is said to develop when the blood level of glucose (the major source of energy to human cells) falls below a critical level of 2.2mmol/L. It is not a disease entity but a biochemical abnormality whose importance is on its effect on the brain.

Such effect is due to the fact that the brain is an obligate user of glucose and virtually depends on it as its source of energy and thus reduction of glucose has untoward effect on the brain.

A hypoglycemic headache is often described by patients as a dull throbbing headache that may be felt more around the forehead and temples and it is not the typical migraine headache and it may even cause cluster headaches in some patients. Other symptoms seen with hypoglycemic headaches may include sweating, tremors, palpitation, hunger, altered or change in the level of consciousness, visual disturbance, dizziness, anxiety and feeling of intense hunger.

It is important to note that the mechanisms that cause blood sugar to fall is known but medical science do not completely understand how hypoglycemia brings on the headache. It is postulated that the headaches may be as a result of impaired metabolism by the neuronal cells due to decrease in blood to brain movement of glucose which leads to poor metabolism and excretion of toxins and their accumulation and oxidative stress on the brain cells which may also cause swelling of the brain cells and tension leading to headaches. The headache may also be as the result of interplay between epinephrine and norepinephrine leading to secretion of cytokines that may mediate the headaches.

This is commonly seen in diabetics and may be due to the following:

1. Over treatment with insulin

2. Drug induced which occurs with the following drugs: sulphonylureas, quinine, salicylates, pentamidine

3. Decrease food intake without adjustment/poor adjustment of insulin dose

4. Excessive or prolonged exercise

5. Skipping meals

6. In cases of renal failure leading to poor clearance(excretion) of insulin in the urine leading to a prolonged action time in the blood

7. Excessive alcohol intake

It may also occur in non diabetics but not common after prolonged period of starvation with subsequent reduction in the glucose stored in the liver other causes include: Insulinoma causing and increased level in circulating insulin, endocrine deficiencies and postprandial reactive hypoglycemic conditions.

Diagnosis of hypoglycemia is usually made clinically using the Whipple’s triad which consists of symptoms consistent with hypoglycemia, a low plasma glucose concentration and relief of symptoms after the plasma blood glucose level has been raised. The blood level is usually obtained by doing a random blood sugar test during an episode of suspected hypoglycemia using glucostrips and a glucometer that reads up the value but when possible, a sample for documentation of the plasma glucose concentration by a quantitative analytical method should be obtained prior to treatment.

Eating small quantity of meals but at regular interval, carry a source of fast sugar when traveling or when at the gymnasium but also try to avoid eating lots of processed sugar with more of complex carbohydrate, proper adjustment of insulin dosage after consultation with your physician, avoiding skipping meals, reduction in alcohol consumption.

Treatment during a visit to your physician usually involves urgent infusion of glucose (dextrose) or ingestion of drinks with sugar or glucose tablets with the aim of raising the blood sugar and the headache usually subsides almost immediately after treatment and other accompanying symptoms also abate. You will then be advised by your physician on how you can prevent re-occurrence and a visit to a dietician for meal evaluation may be necessary and often very helpful.