Low Blood Sugar (Hypoglycemia): Causes, Symptoms, and What to Do

Low blood sugar, also known as hypoglycemia, occurs when the level of glucose in your blood drops below what is healthy for you. This can happen for a variety of reasons and can cause a range of symptoms, from mild to severe. This article explores the causes, symptoms, and what you should do if you experience low blood sugar.

What is Hypoglycemia?

Hypoglycemia technically refers to blood glucose levels below 70 mg/dL (3.9 mmol/L), but the exact threshold at which symptoms appear can vary from person to person. Glucose is the primary source of energy for your body's cells, especially brain cells. Therefore, when glucose levels are too low, your brain and other organs don’t function optimally.

Causes of Low Blood Sugar

Several factors can lead to low blood sugar. These include:

• Diabetes Medications: Insulin and some oral diabetes medications (like sulfonylureas) can cause blood sugar to drop too low if the dose is too high, the timing is off, or if meals are skipped.
• Skipping Meals or Eating Too Little: If you don't eat enough carbohydrates or skip meals, your body may not have enough glucose to maintain normal blood sugar levels.
• Increased Physical Activity: Exercise uses up glucose. If you're more active than usual without adjusting your medication or food intake, your blood sugar can drop.
• Alcohol Consumption: Alcohol can interfere with the liver's ability to release glucose into the bloodstream, especially when consumed on an empty stomach.
• Certain Medical Conditions: Kidney disorders, liver disease, hormone deficiencies (like cortisol or growth hormone), and some rare tumors can contribute to hypoglycemia.
• Reactive Hypoglycemia (Postprandial Hypoglycemia): This occurs a few hours after eating, often after a large or high-sugar meal. It may be related to how your body releases insulin after eating.
• Non-Diabetic Hypoglycemia: This is less common but can occur in individuals without diabetes due to various underlying conditions, including the ones listed above.

Symptoms of Hypoglycemia

Symptoms of low blood sugar can range from mild to severe and can vary from person to person. It's important to recognize these symptoms early and take appropriate action. Common symptoms include:

• Shakiness or Trembling
• Sweating
• Dizziness or Lightheadedness
• Rapid Heartbeat (Palpitations)
• Anxiety or Irritability
• Confusion or Difficulty Concentrating
• Blurred Vision
• Headache
• Hunger
• Weakness or Fatigue

Severe hypoglycemia can lead to:

• Seizures
• Loss of Consciousness
• Coma

What to Do When You Have Low Blood Sugar

If you experience symptoms of hypoglycemia, it's important to act quickly. The "15-15 Rule" is a common guideline:

1. Check your blood sugar (if possible): Use a glucose meter to confirm that your blood sugar is indeed low (below 70 mg/dL).
2. Eat or Drink 15 Grams of Fast-Acting Carbohydrates: Examples include:
   • 3-4 glucose tablets
   • ½ cup (4 ounces) of juice or regular (non-diet) soda
   • 1 tablespoon of honey or syrup
   • Hard candies, jellybeans, or gumdrops (read label to ensure appropriate amount)
3. Wait 15 Minutes: After consuming the carbohydrates, wait 15 minutes.
4. Recheck Your Blood Sugar: If your blood sugar is still below 70 mg/dL, repeat steps 2 and 3.
5. Eat a Meal or Snack: Once your blood sugar is above 70 mg/dL, eat a meal or snack containing both carbohydrates and protein to help stabilize your blood sugar and prevent it from dropping again. Examples include:
   • Peanut butter on crackers
   • Cheese and fruit
   • A handful of nuts with a piece of fruit

If you have severe hypoglycemia and are unable to swallow or are unconscious, someone should administer glucagon, a hormone that raises blood sugar. Family members and close friends of people at risk for severe hypoglycemia should be trained on how to administer glucagon. They should also call emergency services immediately.

Preventing Low Blood Sugar

Preventing hypoglycemia is often easier than treating it. Here are some tips:

• Follow Your Diabetes Management Plan: If you have diabetes, work closely with your healthcare provider to create a diabetes management plan that includes proper medication dosage, meal planning, and exercise guidelines.
• Monitor Your Blood Sugar Regularly: Regularly checking your blood sugar levels can help you identify patterns and adjust your treatment plan as needed.
• Eat Regular Meals and Snacks: Avoid skipping meals or going too long without eating.
• Be Mindful of Carbohydrate Intake: Pay attention to the amount and type of carbohydrates you eat, and balance them with protein and fat.
• Adjust Medication and Food Intake with Exercise: Talk to your doctor about how to adjust your medication and food intake based on your activity level.
• Limit Alcohol Consumption: Drink alcohol in moderation and always with food.
• Carry a Fast-Acting Carbohydrate Source: Always keep a source of fast-acting carbohydrates (such as glucose tablets or juice) with you in case of hypoglycemia.
• Wear a Medical Alert Bracelet or Necklace: This can alert others to your condition if you're unable to communicate.

Diagnostic Tests for Hypoglycemia

If you experience recurrent episodes of low blood sugar, even if you don't have diabetes, your doctor may recommend diagnostic tests to identify the underlying cause. These tests can include:

• Fasting Blood Glucose Test: Measures your blood sugar after an overnight fast.
• Oral Glucose Tolerance Test (OGTT): Measures your blood sugar at regular intervals after you drink a sugary drink.
• Mixed-Meal Tolerance Test (MMTT): Similar to the OGTT, but uses a standardized meal to stimulate insulin release.
• Insulin and C-Peptide Levels: Measure the levels of insulin and C-peptide (a byproduct of insulin production) in your blood to help determine if your body is producing too much insulin.
• Imaging Studies: In rare cases, imaging studies (such as CT scans or MRIs) may be needed to look for tumors that can cause hypoglycemia.

When to See a Doctor

You should see a doctor if:

• You experience frequent episodes of low blood sugar.
• You have symptoms of hypoglycemia and don't have diabetes.
• Your diabetes management plan is not effectively preventing hypoglycemia.
• You've had a severe episode of hypoglycemia that required assistance from someone else.

Early diagnosis and appropriate management are essential for preventing serious complications associated with low blood sugar. It's crucial to work with your healthcare provider to develop a personalized plan that addresses your specific needs.

Types of Fast-Acting Carbohydrates