Hypoglycemic Episode: What to Do If It Happens to You

Hypoglycemia is a potentially dangerous medical condition that occurs when your blood glucose (sugar) levels are too low. A blood glucose level of less than 70 mg/dl is considered low, or hypoglycemic.

Hypoglycemia usually happens to people with diabetes when they have a mismatch of medicine, food, and/or exercise. In rare cases, it may occur in those who do not have diabetes, a condition called non-diabetic hypoglycemia. Non-diabetic hypoglycemia is distinctly different from classic hypoglycemia in that symptoms of low blood sugar are quickly resolved after eating sugar.

This article discusses hypoglycemic episode symptoms and how to treat them. It also details when to seek medical care for hypoglycemia.

woman checking blood sugar

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Hypoglycemic Episode Symptoms

If you have diabetes, frequent bouts of hypoglycemia can be dangerous, potentially increasing your risk of illness or death. This is especially true in those with heart disease.

Recognizing low blood sugar is important because it can help you to take immediate steps toward preventing a medical emergency.

The first symptoms of low blood sugar are:

  • Shaking
  • Sweating
  • Rapid heartbeat
  • Change in vision
  • Hunger
  • Headache
  • Sudden moodiness or irritability

If hypoglycemia is not treated, the plummeting blood sugar levels may lead to severe symptoms requiring immediate medical attention. These symptoms include:

  • Behavior changes
  • Lack of coordination
  • Inattention and confusion
  • Seizures
  • Loss of consciousness

Balancing Glucose Levels

Glucose is the main source of energy for your body and brain. It comes from what we eat and drink. Having a balanced, low-sugar diet is important to maintaining your overall health, especially in those with diabetes.

Insulin, a hormone, helps keep blood glucose at normal levels so your body can work properly. Insulin’s job is to help glucose enter your cells where it’s used for energy. When you exercise, your muscles take up sugar from the blood into the muscle tissue without the need for insulin.

The body also learns to use blood glucose more efficiently when you exercise. Sometimes skipping a meal or overdoing your exercise can cause your blood sugar levels to plummet. When they do, you might not feel well. Therefore, monitoring your symptoms is key to avoiding life-threatening complications. 

How Long Does a Hypoglycemic Episode Last?

The duration of hypoglycemic episodes varies depending on the cause of the event.

  • If the hypoglycemic attack is triggered by overdoing your exercise routine, skipping a meal, or taking too much short-acting insulin, the condition usually improves within minutes by eating or drinking a food or beverage that contains sugar, like a piece of hard candy or orange juice.
  • Hypoglycemia caused by sulfonylurea or long-acting insulin may take longer to resolve but usually goes away in one to two days.

People with diabetes remain at risk for episodes of hypoglycemia throughout life because they need medications that lower blood sugar. The one exception is individuals with type 2 diabetes who manage their condition with lifestyle changes or blood sugar normalizing medications—such as metformin—alone. This group tends to have higher blood sugar levels (hyperglycemia).

When to Check Your Blood Sugar

The most important times to check your blood sugar are first thing in the morning and at night, although it is advised that you check multiple times a day if you are frequently hypoglycemic.

Some of the most concerning hypoglycemic episodes are the ones that occur without your knowledge. When hypoglycemia occurs while sleeping, blood sugar levels remain low and without treatment. If this becomes the norm, it can lead to impaired brain function. 

Tips to Maintain Glucose Levels to Avoid an Attack

A normal blood sugar level for an adult is between 70 and 130 mg/dL before a meal and less than 100 mg/dL when fasting. After a meal, a normal blood sugar level rises to below 180 mg/dL. To avoid hypoglycemia, one’s blood sugar must be above 70 mg/dL, but not above 180 mg/dL at any point as this may lead to hyperglycemia.

The body does not produce an adequate amount of insulin in those with type 1 diabetes, so the body is unable to tightly regulate blood sugar.

People with diabetes should always have ready access to emergency supplies for treating unexpected episodes of hypoglycemia. These supplies may include:

  • Candy
  • Sugar tablets
  • Sugar paste in a tube
  • Non-diet soda
  • Glucagon injection kit

A glucagon injection is mainly used in severe cases of hypoglycemia. It is imperative that a knowledgeable family member or friend learn how to use the glucagon injection kit so that they can use it in the case of an emergency, like when a person is unconscious and cannot take sugar by mouth. For diabetic children, emergency supplies can be kept in the school nurse’s office.

Knowing the triggers that precipitate your hypoglycemic attacks may be key to preventing an attack, but regulating your blood sugars throughout the day can help mitigate chronic deterioration of your health.

Alcohol and Hypoglycemic Attacks

Drinking alcohol has been shown to trigger hypoglycemic attacks even in individuals with diabetes who have taken their insulin hours before. People with diabetes should be very aware of this possible problem if they drink.

If you are at risk of hypoglycemic episodes, you can avoid delays in treating attacks by closely monitoring your symptoms and sharing this knowledge with friends and family members. Not only can they help you if you are feeling ill, but they can also remind you to engage in health-positive behaviors when you fall off the wagon or forget. The risk for hypoglycemia is lower if you:

  • Eat at regular times during the day
  • Never skip meals
  • Maintain a consistent exercise level

In rare circumstances, a healthcare provider may prescribe a glucagon emergency kit for non-diabetic people who have a history of becoming disoriented or losing consciousness from hypoglycemia.

If you have been diagnosed with diabetes, there are ways to prevent hypoglycemia:

  • Eat at least three evenly spaced meals each day, with between-meal snacks as prescribed.
  • Plan your meals no more than four to five hours apart.
  • Exercise routinely, preferably 30 minutes to one hour after meals, and check your sugars before and after exercise.
  • Double-check your insulin and dose of diabetes medicine before taking it.
  • Limit alcohol.
  • Check your blood sugar as often as directed by a healthcare professional.
  • If possible, make routine visits to a primary care health center and keep them abreast of changes in your diet, medication regimen, and how you feel.
  • Know when your medicine is at its peak level.
  • Carry an identification bracelet that says you have diabetes.

An increasing body of evidence suggests that hypoglycemia is harmful to people with diabetes both immediately and over time, as it may have negative impacts on the heart and blood vessels.

Symptoms of hypoglycemia may be vague or mimic other conditions, so you may be unaware of its harmful effects until it’s too late, underscoring the importance of regulating one’s glucose levels even if you are not feeling terribly sick.

When to See a Healthcare Provider

If you are diabetic and you are feeling symptoms of fatigue, weakness, confusion, or a rapid heartbeat, you may be having a hypoglycemic attack and you should seek immediate medical attention.

Share Information With Family and Friends

Severe hypoglycemia can render you unconscious or too weak to seek help, so it is important to share information about your condition with a trusted friend or family member who is willing to help in the event of an emergency.

Even if you do not have diabetes, hypoglycemia can be life-threatening, especially if it is not resolved quickly after eating or drinking a food or beverage with sugar.

There are two kinds of non-diabetic hypoglycemia:

  • Reactive hypoglycemia, which usually happens within a few hours of eating a meal
  • Fasting hypoglycemia, which may be related to a more serious condition

If you are experiencing hypoglycemic symptoms while fasting, you may want to check in with your healthcare provider as this may be indicative of a more serious condition. Tests may need to be done to uncover the underlying cause of your hypoglycemia. Causes of non-diabetic hypoglycemia include: 

  • Binge drinking alcohol
  • Medication (malaria medications and certain antibiotics like Trimethoprim-sulfamethoxazole)
  • Anorexia
  • Hepatitis
  • Adrenal or pituitary gland disorders
  • Kidney failure or acute kidney injury
  • Pancreatic tumors, such as insulinomas or insulin-producing tumors

A Word From Verywell

Hypoglycemia can have an insidious impact on your health, so monitoring your blood sugar even when you are not feeling symptoms is the key to preserving your health.

If you are experiencing symptoms of a hypoglycemic attack, seek immediate medical attention. Untreated hypoglycemia can lead to coma and death.

If you know someone with diabetes who suffers from hypoglycemia, call for emergency medical assistance if they become acutely lethargic, obviously disoriented, or unconscious. Severe insulin reactions can be fatal, so it is important to seek treatment immediately.

Frequently Asked Questions

  • How long does a hypoglycemic episode last?

    Hypoglycemic episodes will last until they are treated with glucose. The general rule of thumb is to have 15 grams of fast-acting carbohydrates and to wait 15 minutes to test your blood sugar to ensure it has risen above 70 mg/dL. If it hasn't, consume another 15 grams of fast-acting carbs and test again in 15 minutes.

  • What should I eat after a hypoglycemic episode?

    Fast-acting sugar is used to treat hypoglycemia. This can be juice, non-diet soda, sugar, fresh or dried fruits, candy, or glucose tabs.

    Once your blood sugar is stable, it is commonly recommended to have a little protein, such as a spoonful of peanut butter, to stabilize blood glucose levels and prevent it from going low again. However, research suggests this is not necessary as protein and fat have minimal effect on blood sugar.

  • How long does it take for a glucagon injection to work?

    Glucagon is given to treat a severe hypoglycemic episode where the person is unconscious and unable to eat or drink to treat low blood sugar. It should take about 15 minutes for a person to regain consciousness after a glucagon injection. If the person does not respond in 15 minutes, a second injection may be needed.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Shamard Charles, MD, MPH
Shamard Charles, MD, MPH is a public health physician and journalist. He has held positions with major news networks like NBC reporting on health policy, public health initiatives, diversity in medicine, and new developments in health care research and medical treatments.