Published: 18 Jun 2025

ICD9: 251.2      ICD10: E16.2      ICD11: 5A41

Hypoglycemia, also known as low blood sugar, happens when the glucose (sugar) level in your blood drops too low.
Glucose is your body's main source of energy.

Here's a breakdown:

What it is: A condition where your blood glucose levels fall below what your body needs to function properly. The specific threshold for "low" can vary, but generally it's considered below 70 mg/dL (3.9 mmol/L).

Causes:

Diabetes Medications: Most commonly, hypoglycemia is a side effect of medications used to treat diabetes, such as insulin and certain oral medications (sulfonylureas). Too much medication, taking it without enough food, or exercising strenuously after taking the medication can lead to a drop in blood sugar.
Skipping Meals or Eating Too Little: Not eating enough or skipping meals can deplete glucose stores in your body.
Excessive Exercise: Strenuous or prolonged physical activity can use up glucose faster than it can be replaced, especially if you don't adjust your food intake or medication.
Alcohol Consumption: Alcohol can interfere with the liver's ability to release stored glucose into the bloodstream, especially when consumed without food.
Certain Medical Conditions: Rarely, hypoglycemia can be caused by other medical conditions such as:
Kidney or liver disease
Hormone deficiencies (e.g., adrenal insufficiency)
Certain tumors (e.g., insulinomas)
Reactive Hypoglycemia (Postprandial Hypoglycemia): This occurs in people who don't have diabetes, and happens a few hours after eating a meal. The exact cause is often unknown, but it may be related to rapid gastric emptying or overproduction of insulin in response to a meal high in carbohydrates.

Symptoms: Symptoms can vary from person to person and can depend on how quickly the blood sugar drops. They may include:

Mild to Moderate:
Shakiness or trembling
Sweating
Hunger
Dizziness or lightheadedness
Headache
Blurred vision
Confusion
Irritability or anxiety
Rapid heartbeat
Weakness

Severe:
Loss of coordination
Difficulty speaking
Seizures
Loss of consciousness (coma)
Can be life-threatening

Treatment:

Mild to Moderate: The immediate goal is to raise blood sugar levels quickly. This can be done by:
Eating or drinking 15-20 grams of fast-acting carbohydrates, such as:
* Glucose tablets or gel
* Fruit juice (1/2 cup)
* Regular (non-diet) soda (1/2 cup)
* Hard candies (check the label for carbohydrate content)
Wait 15 minutes and recheck blood sugar. If it's still low, repeat the treatment.

Severe: If someone is unconscious or unable to swallow, they may need:
Glucagon injection (a hormone that raises blood sugar). This is typically administered by someone who has been trained.
Intravenous (IV) glucose in a hospital setting.

Prevention:

For people with diabetes:
Carefully follow your doctor's instructions for medication, diet, and exercise.
Monitor blood sugar levels regularly.
Don't skip meals.
Adjust medication or food intake when exercising.
Be aware of the signs and symptoms of hypoglycemia.
Carry a source of fast-acting carbohydrates with you at all times.
Wear medical identification (e.g., a bracelet or necklace) indicating that you have diabetes.
For people without diabetes:
Eat regular meals and snacks.
Avoid excessive alcohol consumption, especially without food.
If you experience symptoms of hypoglycemia, talk to your doctor to rule out any underlying medical conditions.

Important Considerations:

Hypoglycemia can be dangerous, especially if left untreated. Severe hypoglycemia can lead to seizures, coma, and even death.
If you have diabetes, it's important to work closely with your doctor or diabetes educator to develop a management plan that helps you prevent hypoglycemia.
If you experience frequent episodes of hypoglycemia, even if you don't have diabetes, see your doctor to determine the cause and receive appropriate treatment.

Disclaimer: This information is for general knowledge and informational purposes only, and does not constitute medical advice. It is essential to consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.