Living with Type 1 diabetes (T1D) means constantly managing blood sugar levels to stay within a safe range. However, there are times when blood sugar levels can veer too low (hypoglycemia) or too high (hyperglycemia). Understanding these two extremes—what they are, why they happen, and how to manage them—is crucial for maintaining your health and well-being.

What Is Hypoglycemia (Low Blood Sugar)?

Hypoglycemia occurs when your blood sugar level drops below the target range, typically below 70 mg/dL (3.9 mmol/L). It’s often referred to as a “hypo.”

Causes of Hypoglycemia

• Too Much Insulin: Injecting more insulin than your body needs for the amount of carbs you’ve eaten.
• Skipping Meals or Snacks: Missing food after taking insulin can cause a drop in blood sugar.
• Excessive Exercise: Physical activity uses up glucose, which can lead to a low if not accounted for.
• Alcohol Consumption: Alcohol can block the liver from releasing glucose into the bloodstream, causing delayed hypoglycemia.

Symptoms of Hypoglycemia

• Shakiness
• Sweating
• Dizziness or lightheadedness
• Rapid heartbeat
• Hunger
• Irritability or mood changes
• Confusion or difficulty concentrating

In severe cases, untreated hypoglycemia can lead to fainting, seizures, or loss of consciousness.

What Is Hyperglycemia (High Blood Sugar)?

Hyperglycemia happens when your blood sugar level rises above the target range, usually over 180 mg/dL (10 mmol/L) after meals. It’s often referred to as a “hyper.”

Causes of Hyperglycemia

• Insufficient Insulin: Not taking enough insulin to cover the carbs you’ve eaten.
• Illness or Stress: Both can cause the body to release hormones that raise blood sugar levels.
• Overeating Carbohydrates: Consuming more carbs than planned can lead to a spike.
• Inactivity: Lack of exercise can make it harder for your body to use glucose efficiently.

Symptoms of Hyperglycemia

• Increased thirst
• Frequent urination
• Fatigue or tiredness
• Blurred vision
• Dry mouth
• Headaches

If left untreated, hyperglycemia can lead to serious complications such as diabetic ketoacidosis (DKA), which is a medical emergency.

Why Managing Blood Sugar Matters

Both hypo- and hyperglycemia can have short- and long-term effects on your health. Short-term, they can disrupt your daily life and make it hard to function. Long-term, frequent or prolonged highs or lows can damage your nerves, blood vessels, and organs, increasing the risk of complications like heart disease, kidney damage, or vision problems.

How to Manage Hypoglycemia and Hyperglycemia

Treating Hypoglycemia

1. Check Your Blood Sugar: If you feel low, confirm it with your CGM or glucometer.
2. Consume Fast-Acting Glucose: Take 15 grams of quick carbs like:
   • Glucose tablets or gel
   • 4 oz (120 mL) of juice
   • 1 tablespoon of honey or sugar
3. Recheck Your Blood Sugar After 15 Minutes: If it’s still low, repeat the treatment.
4. Eat a Snack or Meal: Once your blood sugar is back in range, eat something with carbs and protein to stabilize levels.

Pro Tip: Always carry fast-acting glucose with you, especially during exercise or long outings.

Managing Hyperglycemia

1. Check Your Blood Sugar: Confirm the high with your CGM or glucometer.
2. Take a Correction Dose of Insulin: Based on your insulin-to-blood-sugar correction ratio.
3. Drink Water: Staying hydrated helps flush excess glucose from your bloodstream.
4. Be Active: Light exercise can help bring blood sugar down, but avoid this if ketones are present.
5. Monitor for Ketones: If your blood sugar is above 250 mg/dL (13.9 mmol/L), test for ketones. If ketones are present, seek medical advice immediately.

Pro Tip: Avoid overcorrecting with insulin to prevent a rebound hypo.

How to Prevent Hypoglycemia and Hyperglycemia

• Monitor Blood Sugar Frequently: Use a CGM or glucometer to stay on top of your levels.
• Stick to a Routine: Consistent eating, insulin dosing, and exercise can help maintain stable blood sugar.
• Adjust for Changes: Account for stress, illness, or increased activity by tweaking your insulin or carb intake.
• Work with Your Healthcare Team: Regular check-ins with your doctor or diabetes educator ensure your management plan is up to date.

Living Alone with T1D: Planning for Emergencies

If you live alone, hypo- and hyperglycemia can feel even more daunting. Having a solid emergency plan in place is essential. For tips on preparing for and managing these situations solo, check out our blog: Planning for Hypoglycemia and Hyperglycemia When Alone.