Hypoglycemia Explained: Signs of Low Blood Sugar and What to Do

23 Aug 2025

Hypoglycemia Explained: Signs of Low Blood Sugar and What to Do Hypoglycemia, or low blood sugar, is a condition that occurs when the level of glucose...

Hypoglycemia Explained: Signs of Low Blood Sugar and What to Do

Hypoglycemia, or low blood sugar, is a condition that occurs when the level of glucose (sugar) in your blood drops too low. It's more common among people with diabetes, especially those taking insulin or certain oral medications. However, it can also happen in people without diabetes due to various factors. Understanding the signs and knowing what to do is crucial for managing and preventing serious complications.

What is Hypoglycemia?

Essentially, hypoglycemia means that your brain and body aren't getting enough glucose, which is their primary source of energy. When blood sugar levels fall below a certain threshold (typically below 70 mg/dL), it triggers various symptoms. It's important to note that the specific blood sugar level that causes symptoms can vary from person to person. Some individuals might experience symptoms at higher levels than others. Therefore, consistent blood glucose monitoring is important, particularly if you have diabetes.

Causes of Hypoglycemia

While often associated with diabetes management, hypoglycemia can stem from several factors:

  • Diabetes Medications: Overdosing on insulin or certain oral diabetes medications that stimulate insulin production (sulfonylureas, meglitinides) are the most frequent causes of hypoglycemia in people with diabetes.
  • Skipping Meals or Delaying Meals: Not eating regularly or skipping meals can cause blood sugar levels to drop.
  • Excessive Exercise: Strenuous physical activity without adequate carbohydrate intake can deplete glucose stores.
  • Alcohol Consumption: Alcohol can interfere with the liver's ability to release glucose into the bloodstream, particularly when consumed on an empty stomach.
  • Certain Medical Conditions: Some kidney, liver, or adrenal gland disorders can lead to hypoglycemia.
  • Insulinoma: This is a rare tumor of the pancreas that produces excess insulin.
  • Reactive Hypoglycemia: This occurs within a few hours after eating a meal, particularly one high in carbohydrates. The exact cause isn't fully understood, but it might involve an overreaction of insulin release.
  • Post-Bariatric Surgery: Changes to the digestive system following bariatric surgery can affect blood sugar regulation.

Signs and Symptoms of Hypoglycemia

The symptoms of hypoglycemia can vary from mild to severe. It’s vital to recognize these signs and take action quickly. Here are some common symptoms:

Related reading: How To Manage Blood Sugar A Beginner S Guide To Diet And Exercise

  • Mild to Moderate Symptoms:

    • Shakiness or trembling
    • Sweating
    • Rapid heartbeat
    • Anxiety or nervousness
    • Irritability or confusion
    • Dizziness or lightheadedness
    • Blurred vision
    • Headache
    • Hunger
    • Weakness

    • Severe Symptoms (requiring immediate medical attention):

    • Confusion or difficulty concentrating

    • Slurred speech
    • Seizures
    • Loss of consciousness
    • Inability to eat or drink

It is very important to remember that a person can lose consciousness if hypoglycemia is not treated quickly. If a person with diabetes has passed out, they will require a glucagon injection or need immediate medical attention at the nearest hospital or emergency center.

Diagnosing Hypoglycemia

A doctor will typically diagnose hypoglycemia based on your symptoms, medical history, and blood sugar levels. The following criteria, known as Whipple's triad, are often used:

  1. Symptoms of hypoglycemia
  2. Documented low blood glucose level (typically less than 70 mg/dL) at the time of the symptoms
  3. Relief of symptoms when blood glucose level is raised

In some cases, a doctor may order further tests, such as a mixed-meal tolerance test, to evaluate how your body processes glucose. This can be especially helpful in diagnosing reactive hypoglycemia.

Related reading: Feeling Shaky And Anxious Understanding The Signs Of Low Blood Sugar Hypoglycemia

What to Do When You Experience Hypoglycemia

If you suspect you have hypoglycemia, take these steps:

  1. Check Your Blood Sugar (if possible): Use a blood glucose meter to confirm that your blood sugar is low (below 70 mg/dL).

  2. The 15-15 Rule: If your blood sugar is low, consume 15 grams of fast-acting carbohydrates, such as:

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    • 4 ounces (1/2 cup) of juice or regular (non-diet) soda
    • Glucose tablets (follow package instructions for 15 grams)
    • 1 tablespoon of honey or sugar
    • Hard candies (check the package for equivalent carbs)
    • Wait 15 Minutes: After consuming the carbohydrates, wait 15 minutes and then recheck your blood sugar.
    • Repeat if Necessary: If your blood sugar is still low (below 70 mg/dL), repeat steps 2 and 3 until your blood sugar rises to a safe level.

    • Eat a Snack or Meal: Once your blood sugar is back within a normal range, eat a snack or meal to help stabilize your blood sugar and prevent another drop. Choose a snack or meal that contains both carbohydrates and protein, such as:

    • Crackers with peanut butter

    • Cheese and fruit
    • Yogurt with granola
    • Emergency Situations: If someone is experiencing severe symptoms such as seizures or loss of consciousness, administer glucagon (if available and you know how to use it) and call emergency services immediately (911 in the US). DO NOT attempt to give an unconscious person anything by mouth due to the risk of choking.

Preventing Hypoglycemia

Prevention is key to managing hypoglycemia. Here are some helpful strategies:

  • Regular Blood Glucose Monitoring: If you have diabetes, monitor your blood sugar levels regularly as directed by your doctor. Keep a log of your readings to help identify patterns and potential triggers.
  • Follow Your Meal Plan: Eat regular meals and snacks at consistent times throughout the day. Don't skip meals or delay them for extended periods.
  • Adjust Insulin Doses: Work closely with your doctor or diabetes educator to adjust your insulin doses as needed based on your blood sugar levels, diet, and activity level.
  • Learn to Recognize Symptoms: Become familiar with the early signs of hypoglycemia so you can take action promptly.
  • Carry a Source of Fast-Acting Carbohydrates: Always have a source of fast-acting carbohydrates with you, such as glucose tablets, juice boxes, or hard candies.
  • Inform Others: Educate your family, friends, and coworkers about the signs of hypoglycemia and what to do in an emergency. Consider wearing a medical ID bracelet or necklace that indicates you have diabetes and are prone to hypoglycemia.
  • Be Mindful of Alcohol Consumption: If you drink alcohol, do so in moderation and always consume it with food. Avoid drinking on an empty stomach.
  • Exercise Safely: Before engaging in physical activity, check your blood sugar and eat a snack if needed. Monitor your blood sugar during and after exercise, and adjust your insulin or carbohydrate intake accordingly.

Hypoglycemia Treatment Options

The primary treatment for hypoglycemia involves quickly raising blood sugar levels with fast-acting carbohydrates. However, in severe cases, medical intervention may be necessary. Here are some treatment options:

  • Oral Glucose: For mild to moderate hypoglycemia, consuming oral glucose (glucose tablets, juice, or sugar) is usually sufficient to raise blood sugar levels.
  • Glucagon Injection: Glucagon is a hormone that stimulates the liver to release stored glucose into the bloodstream. It's available as an injectable medication and is used to treat severe hypoglycemia when a person is unable to take oral glucose due to unconsciousness or seizures. Family members or caregivers should be trained on how to administer glucagon in an emergency.
  • Intravenous Glucose: In the hospital setting, intravenous (IV) glucose may be administered to quickly raise blood sugar levels in severe cases of hypoglycemia.

Long-Term Management

In addition to treating episodes of hypoglycemia, long-term management involves identifying and addressing the underlying causes. If you have diabetes, this may involve adjusting your medication regimen, modifying your diet, or altering your exercise routine. For people without diabetes, further evaluation may be needed to rule out underlying medical conditions that could be contributing to hypoglycemia.

Understanding How Food Impacts Blood Sugar

Food plays a huge role in controlling blood sugar levels and preventing episodes of hypoglycemia.

Food Type Impact on Blood Sugar Examples
Simple Carbohydrates Rapidly raise blood sugar levels; provide a quick source of energy, but the effect is often short-lived. Can lead to blood sugar "spikes" and subsequent drops. Juice, soda, candy, table sugar
Complex Carbohydrates Raise blood sugar levels more slowly and gradually than simple carbohydrates; provide a sustained release of energy. Whole grains (brown rice, quinoa, oats), starchy vegetables (potatoes, corn), beans, lentils
Protein Has a minimal effect on blood sugar levels; helps to stabilize blood sugar when eaten with carbohydrates. Meat, poultry, fish, eggs, tofu, beans, nuts, seeds
Fat Has a minimal effect on blood sugar levels; can slow down the absorption of carbohydrates, which helps to prevent blood sugar spikes. Avocados, nuts, seeds, olive oil, fatty fish

Conclusion

Hypoglycemia can be a concerning condition, especially for individuals with diabetes. Recognizing the signs, knowing what to do in an emergency, and taking preventive measures are essential for managing and preventing hypoglycemia. If you frequently experience low blood sugar levels, work with your doctor or a diabetes educator to identify the underlying causes and develop a personalized management plan. With proper knowledge and proactive management, you can minimize the risk of hypoglycemia and maintain stable blood sugar levels.