Understanding Hypoglycemia (Low Blood Sugar): Causes, Symptoms, Treatment

Introduction

Hypoglycemia, or low blood sugar, occurs when your blood glucose drops below 70 mg/dL. It’s a common but potentially serious issue, especially for people with diabetes who use insulin or other glucose-lowering medications. If untreated, it can lead to confusion, unconsciousness, seizures, or even death.

This guide explains what hypoglycemia is, why it happens, how to spot it early, and how to treat it safely and effectively.

What Is Hypoglycemia?

Hypoglycemia happens when the level of glucose (sugar) in your blood drops too low to fuel your body’s activities—especially the brain, which depends heavily on glucose.

Blood Sugar Levels (General Guide):

• Normal fasting: 70–99 mg/dL
• Hypoglycemia: Below 70 mg/dL
• Severe hypoglycemia: Below 54 mg/dL

Common Causes of Hypoglycemia

1. Too much insulin or diabetes medication

• Taking more insulin or sulfonylureas than needed can cause blood sugar to drop too low.

2. Skipping or delaying meals

• Not eating after taking medication can lead to hypoglycemia.

3. Increased physical activity

• Exercise uses up glucose; without proper fueling, this can cause low blood sugar.

4. Alcohol consumption

• Especially when consumed without food, alcohol can block glucose release from the liver.

5. Illness or hormonal changes

• Can alter how the body processes glucose or insulin.

Symptoms of Hypoglycemia

Recognizing symptoms early is key to preventing serious complications.

Mild to Moderate Symptoms:

• Shaking or trembling
• Sweating
• Hunger
• Headache
• Irritability or mood changes
• Fast heartbeat
• Dizziness or light-headedness
• Blurred vision
• Weakness or fatigue

Severe Symptoms:

• Confusion
• Slurred speech
• Clumsiness
• Seizures
• Loss of consciousness

Note: People who frequently have low blood sugar may develop hypoglycemia unawareness, where symptoms no longer appear clearly—making regular monitoring critical.

How to Treat Hypoglycemia

Step 1: Check Your Blood Sugar

If you feel symptoms, use a glucose meter or continuous glucose monitor (CGM).

Step 2: Follow the 15-15 Rule

1. Eat or drink 15 grams of fast-acting carbohydrates:
   • 4 oz (½ cup) fruit juice or regular soda
   • 3–4 glucose tablets
   • 1 tablespoon of sugar or honey
   • Hard candy (check label for carb content)
2. Wait 15 minutes, then recheck your blood sugar.
3. If still below 70 mg/dL, repeat the 15-15 process.
4. Once blood sugar returns to normal, eat a balanced snack or meal to maintain stability.

Severe Hypoglycemia Treatment:

• If the person is unconscious or unable to swallow:
  • Do not give food or drink
  • Administer glucagon injection or use a nasal glucagon spray (if available)
  • Call emergency medical services (911) immediately

Preventing Hypoglycemia

• Monitor blood sugar regularly, especially during exercise or after insulin doses
• Never skip meals, and match your carb intake to your medications
• Adjust insulin for changes in activity or illness
• Always carry quick sugar sources (like glucose tablets) with you
• Discuss any episodes with your healthcare provider to adjust treatment

Special Considerations

For People with Type 1 Diabetes:

• Hypoglycemia is more common and can be more dangerous
• Use a CGM with alarms if possible
• Be extra cautious during nighttime, post-exercise, and after alcohol

For People with Type 2 Diabetes:

• Hypoglycemia risk is higher if taking insulin or sulfonylureas
• Risk is lower with metformin, GLP-1 receptor agonists, or SGLT2 inhibitors

For Older Adults:

• More susceptible to falls and cognitive decline during hypoglycemia
• May have less obvious symptoms

Conclusion

Hypoglycemia is a serious but manageable condition. Knowing the causes, recognizing the symptoms early, and responding quickly can prevent dangerous outcomes. Whether you’re managing diabetes personally or caring for someone who is, staying informed and prepared is the best defense.

FAQs:

What is considered low blood sugar?

A blood glucose level below 70 mg/dL is considered hypoglycemia.

What are the common symptoms of low blood sugar?

Symptoms include shakiness, sweating, dizziness, irritability, hunger, and confusion.

3. How do I quickly treat low blood sugar?

Follow the 15-15 rule: consume 15g of fast-acting carbs (like juice or glucose tablets), wait 15 minutes, and recheck your blood sugar.

Can hypoglycemia be life-threatening?

Yes, severe hypoglycemia can lead to seizures, unconsciousness, or even death if not treated quickly.

How can I prevent hypoglycemia?

Eat regularly, monitor your blood sugar, adjust medications as needed, and carry fast-acting carbs with you at all times.