Hyperglycemia and hypoglycemia are two conditions that relate to blood sugar levels in the body. Managing these levels is crucial for individuals with diabetes, as both extremes can lead to significant health problems. While hyperglycemia refers to high blood sugar levels, hypoglycemia is characterized by low blood sugar levels.

People with diabetes may experience symptoms of hyperglycemia when blood sugar levels rise above 180 to 200 milligrams per deciliter (mg/dL). At the same time, hypoglycemia typically occurs when fasting blood sugar levels fall below 70 mg/dL.

This article will discuss the causes, symptoms, and treatments of hyperglycemia and hypoglycemia, as well as the importance of blood sugar management for individuals with diabetes. Understanding the differences between these two conditions allows you to take the appropriate steps to prevent and manage blood sugar fluctuations.

Hypoglycemia And Hyperglycemia

What is Hyperglycemia?

Hyperglycemia, or high blood sugar, occurs when too much glucose is in the bloodstream. This condition is typically associated with diabetes, a disease in which the body either does not produce enough insulin or cannot effectively use the insulin it produces. Insulin is a hormone that helps regulate blood sugar levels by allowing glucose to enter the body's cells for energy. When there is insufficient insulin or the body is resistant to insulin, glucose remains in the blood, leading to hyperglycemia.

Several factors can contribute to hyperglycemia, such as eating too many carbohydrates, stress, illness, or insufficient physical activity. People with diabetes must carefully manage their blood sugar levels to avoid hyperglycemia and its potential complications.

Symptoms of hyperglycemia can vary depending on its severity. They typically develop gradually over time and may include:

  • Frequent urination
  • Increased thirst
  • Blurred vision
  • Fatigue
  • Headaches

It is important to note that hyperglycemia typically does not cause symptoms until blood sugar levels are significantly high, usually above 180 to 200 mg/dL. If left untreated, hyperglycemia can lead to serious complications such as damage to blood vessels and nerves, increased risk of infection, and impaired healing.

To prevent and manage hyperglycemia, individuals should:

  • Monitor their blood sugar levels regularly
  • Follow a healthy diet plan
  • Engage in regular physical activity
  • Take medications as prescribed, if necessary
  • Consult with their healthcare team for personalized advice and care.

It is crucial for people with diabetes or at risk of developing diabetes to be aware of hyperglycemia and take proactive measures to maintain healthy blood sugar levels, as prolonged high blood sugar can cause long-term damage to various organs and systems in the body.

What is Hypoglycemia?

Hypoglycemia is when blood sugar levels drop below the standard range, typically less than 70 milligrams per deciliter (mg/dL). This condition occurs when the body has insufficient glucose, its primary energy source, to function properly. Though hypoglycemia is often associated with diabetes treatment, it can also result from other drugs and various conditions, including some rare ones, in people without diabetes.

There are various causes of hypoglycemia, with the most common being a side effect of diabetes medications like insulin. Some other potential causes include:

  • Prolonged fasting or skipping meals
  • Intense exercise without adjusting carbohydrate intake or medication
  • Consumption of alcohol, which can interfere with glucose production in the liver
  • Certain medical conditions, such as hormone deficiencies or kidney and liver diseases

The symptoms of hypoglycemia can vary depending on the severity of the condition and the individual's unique characteristics. However, some common symptoms include:

  • Shakiness or trembling
  • Sweating
  • Feeling lightheaded or dizzy
  • Confusion
  • Hunger
  • Headaches
  • Irritability and mood changes

Treatment for hypoglycemia involves raising blood sugar levels by consuming carbohydrates, such as fruit, fruit juice, or glucose tablets. In more severe cases, medical professionals may administer intravenous glucose or injectable glucagon. To prevent hypoglycemia, individuals must monitor their blood sugar levels, especially if they have diabetes, and follow their healthcare team's guidance to ensure proper medication dosage and meal planning.

Understanding Hyperglycemia and Hypoglycemia

Causes of Hyperglycemia

Hyperglycemia is a condition where the blood sugar level is too high. It can occur in people with diabetes when they do not produce enough insulin, a hormone responsible for regulating blood glucose levels, or when the body cannot use insulin effectively. This high blood sugar can result from various factors, such as:

  • Insufficient insulin production by the pancreas
  • Insulin resistance in people with type 2 diabetes
  • Overconsumption of carbohydrates or sugar-laden foods
  • Not enough insulin properly being injected when eating carbohydrates
  • Stress, illness, or infection
  • Medications that raise blood sugar levels
  • Inactivity or lack of exercise

When fasting, blood glucose levels are consistently above 130 mg/dL; it is considered hyperglycemia. If left untreated, hyperglycemia can damage organs, blood vessels, nerves, and tissues, making the individual more susceptible to complications such as cardiovascular disease, strokes, and digestive and kidney diseases.

Causes of Hypoglycemia

Hypoglycemia, on the opposite end of the spectrum, refers to low blood sugar levels. It typically occurs when blood sugar levels drop below 70 mg/dL. This can happen in people with diabetes for several reasons, including:

  • Taking too much insulin or other blood sugar-lowering medications
  • Skipping or delaying meals
  • Engaging in intense physical activity without proper adjustments to food intake or insulin dosage
  • Drinking alcohol without consuming enough carbs to level the alcohol

In some instances, hypoglycemia can also affect individuals without diabetes. This is usually due to an overproduction of insulin by the pancreas or an imbalance in the hormones that regulate glucose metabolism in the liver.

Both hyperglycemia and hypoglycemia can cause major health problems if not adequately managed. People with diabetes must closely monitor their blood sugar levels and follow their healthcare team's advice to prevent these potentially harmful situations.

Symptoms and Diagnosis of Hyperglycemia/Hypoglycemia

This section will discuss the symptoms and diagnosis of both hyperglycemia and hypoglycemia, which are high and low blood sugar levels.

Symptoms of Hyperglycemia

Hyperglycemia occurs when there is an excessive amount of glucose in the blood. The symptoms of hyperglycemia typically develop slowly over several days or weeks. Some common symptoms of hyperglycemia include:

  • Fatigue and headache
  • Frequent urination
  • Increased thirst
  • Nausea and vomiting
  • Shortness of breath
  • Confusion and coma

If left untreated, these symptoms can progress and give rise to serious complications, such as neuropathy and infection.

Symptoms of Hypoglycemia

Hypoglycemia, on the other hand, is a condition where the glucose levels in the blood are lower than normal. The symptoms of hypoglycemia are often more immediate than those of hyperglycemia and can include:

  • Anxiety and nervousness
  • Blurred or impaired vision
  • Pale skin
  • Confusion and coordination problems
  • Dizziness and lightheadedness
  • Fast heartbeat and headaches
  • Hunger and low energy
  • Nausea and seizures
  • Sleepiness and shakiness


When diagnosing hyperglycemia or hypoglycemia, it is essential to monitor blood sugar levels regularly. For hyperglycemia diagnosis, blood sugar levels usually don't cause symptoms until they are above 180mg/dL to 200mg/dL. On the other hand, hypoglycemia diagnosis typically occurs when blood sugar levels are significantly lower than 70 mg/dL.

To manage and avoid long-term complications of high and low blood sugar levels, the American Diabetes Association recommends target blood sugar levels as follows:

  • Between 80 and 130 mg/dL (4.4 and 7.2 mmol/L) before meals
  • Less than 180 mg/dL (10 mmol/L) two hours after meals

These target ranges may differ according to an individual's health status and other factors, such as pregnancy or existing health problems caused by diabetes.

Treatment and Management

Hyperglycemia Treatment

Hyperglycemia, or high blood sugar, can result from various factors, such as insufficient insulin, poor diet, or stress. Treatment for hyperglycemia typically involves adjusting medications, incorporating regular exercise, and maintaining a healthy diet.

Severe hyperglycemia can lead to diabetic ketoacidosis, a life-threatening condition requiring immediate medical attention. Signs of severe hyperglycemia include dehydration, abdominal pain, and increased blood glucose levels.

Hypoglycemia Treatment

Hypoglycemia, or low blood sugar, can be treated by adhering to the 15-15 rule. This involves consuming 15 grams of carbohydrates and waiting 15 minutes before rechecking blood sugar levels. If blood glucose levels remain below 70 mg/dL, repeat the process until they improve.

Glucose tablets, snacks, or drinks can provide quick relief from hypoglycemia. In some cases, a glucagon injection may be necessary, especially if the individual is unconscious or unable to consume carbohydrates.

How can I tell the difference between high and low blood sugar levels?

High blood sugar (hyperglycemia) symptoms include increased thirst, frequent urination, fatigue, and blurred vision. In contrast, low blood sugar (hypoglycemia) manifests as weakness, shakiness, sweating, and confusion. It is essential for individuals with diabetes or prediabetes to monitor their blood sugar levels regularly using a continuous glucose monitor or other testing methods.

Preventing Hypoglycemia and Hyperglycemia

To prevent hypoglycemia and hyperglycemia, focus on managing diabetes through proper medication, diet, and exercise. Key strategies include:

  • Work closely with your healthcare provider to adjust medications as needed
  • Plan meals and snacks with controlled carbohydrate content
  • Monitor blood glucose levels regularly and adjust treatment plans accordingly
  • Incorporate regular exercise into your daily routine
  • Avoid excessive alcohol consumption
  • Discuss major lifestyle changes, such as surgery or fasting, with your healthcare provider

By adhering to these guidelines and maintaining open communication with your health care provider, individuals can effectively manage their blood sugar levels and reduce the risk of complications related to hypoglycemia and hyperglycemia.

Diet and Lifestyle

Diabetic Meal Planning

Diabetic meal planning involves balancing carbohydrates, proteins, and fats to maintain healthy blood sugar levels. Consuming meals focusing on fruits, vegetables, and whole grains can contribute to a nutritious and balanced diet for individuals with diabetes. Monitoring carbohydrate intake is crucial, as it is the main factor that affects blood glucose levels. A diabetes diet should be naturally rich in nutrients and low in fat and calories.

When selecting carbohydrates, it is essential to consider complex carbohydrates, such as whole grains and legumes, which do not spike blood glucose and improve glycemic control. Skipping meals or improper coordination between meals and diabetes medication may lead to severe hypoglycemia or hyperglycemia.

Exercise and Physical Activity

Increased physical activity can help lower blood glucose levels and contribute to overall diabetes management. Regular physical activity, at least 5 days per week, can help prevent hyperglycemia and reduce the risk of obesity, cardiovascular disease, and other diabetes-related complications such as kidney disease or amputation.

Exercise assists the body in using insulin effectively, which enables cells to utilize glucose more efficiently. It is essential to note that physical stress or injury may temporarily elevate blood glucose levels. Hence, monitoring blood glucose before and after exercise is vital to prevent hypoglycemia or hyperglycemia during physical activity.

Other factors to consider in managing blood sugar levels include avoiding smoking, which increases the risk of heart and kidney disease. Additionally, consulting with a dietitian to create a personalized meal plan and incorporating family history into diabetes management can help achieve the desired fasting blood sugar levels.

In conclusion, managing diet and lifestyle is crucial in preventing high blood glucose or severe hypoglycemia in individuals with diabetes. Balanced meal planning and regular physical activity are essential to achieving optimal blood sugar control and preventing complications related to diabetes.



Hyperglycemia occurs when blood sugar levels are consistently high. Various complications can arise from untreated or poorly managed hyperglycemia. Long-term complications can develop slowly, affecting different body parts, including the eyes, kidneys, nerves, and heart.

Long-Term Complications

  • Nerve Damage: Prolonged high blood sugar can cause nerve damage, leading to numbness and pain in the extremities, digestive problems, and more.
  • Kidney Disease: High blood sugar can harm the kidneys, impairing their ability to filter waste from the blood, eventually leading to kidney failure.
  • Eye complications: Diabetic retinopathy, glaucoma, and cataracts result from damage to the retina's blood vessels due to chronically high blood sugar.


Hypoglycemia is low blood sugar, often resulting from an imbalance between insulin, food intake, and physical activity. Hypoglycemia can lead to various complications, including the following:

Long-Term Complications

  • Hypoglycemia Unawareness: Frequent episodes of low blood sugar can increase the risk of hypoglycemia unawareness, where an individual may not recognize early signs and symptoms, further delaying treatment.
  • Dawn Phenomenon: Elevated levels of hormones such as cortisol, growth hormone, and epinephrine can cause blood sugar levels to rise in the early morning, leading to the so-called dawn phenomenon.
  • Worsened Diabetes Management: Persistent hypoglycemia can complicate diabetes management, as fear of low blood sugar may lead to insufficient insulin use, eventually resulting in uncontrolled high blood sugar.

To manage these complications, individuals with diabetes should consider wearing a medical ID to alert others of their condition in emergencies. Regular blood sugar monitoring is essential to detect and address high or low blood sugar early. People with diabetes should also maintain a dialogue with their healthcare providers about adjusting their treatment plans based on changing needs over time.

Frequently Asked Questions

Does type 2 diabetes cause hyperglycemia or hypoglycemia?

Type 2 diabetes typically causes hyperglycemia, which is high blood sugar levels. But can also cause hypoglycemia.

What's worse, hypoglycemia or hyperglycemia?

Both hypoglycemia and hyperglycemia can have serious health consequences, but hypoglycemia can be more immediately dangerous as it can cause seizures, loss of consciousness, and even death if left untreated.

What are the 3 signs of hyperglycemia?

The three signs of hyperglycemia are increased thirst, frequent urination, and blurred vision.

How do I know if I'm hypoglycemic?

If you're hypoglycemic, you may experience symptoms such as shakiness, sweating, dizziness, confusion, and weakness. You may also feel irritable or anxious. It's important to check your blood sugar levels if you suspect you're hypoglycemic and to treat it promptly with a source of glucose, such as fruit juice or candy.


In summary, both hypoglycemia and hyperglycemia affect the regulation of blood sugar levels. Hypoglycemia occurs when blood sugar levels are too low, typically below 70 mg/dL. At the same time, hyperglycemia involves high blood sugar levels that may be diagnosed when fasting blood sugar levels are over 130 mg/dL.

Both conditions can lead to significant health problems, particularly in individuals with diabetes. Some common symptoms of hypoglycemia include confusion, dizziness, and increased heart rate, while hyperglycemia may display symptoms such as frequent urination, increased thirst, and blurred vision.

Proper management of these conditions is crucial for maintaining overall health, especially for those with diabetes. This may involve regularly monitoring blood sugar levels, adhering to prescribed medications, and following a balanced diet and exercise plan.

In conclusion, individuals need to understand the potential risks and symptoms of both hypoglycemia and hyperglycemia. By educating themselves on these conditions and working closely with healthcare professionals, people can better manage their blood sugar levels and strive for optimal health.


At Diabetic Me, we are committed to delivering information that is precise, accurate, and pertinent. Our articles are supported by verified data from research papers, prestigious organizations, academic institutions, and medical associations to guarantee the integrity and relevance of the information we provide. You can learn more about our process and team on the about us page.

  1. Mayo Clinic Hyperglycemia in diabetes
  2. Mayo Clinic Hypoglycemia
  3. Health Line Hyperglycemia vs. Hypoglycemia: What’s the Difference?
  4. Very Well Health Hypoglycemia vs. Hyperglycemia
  5. American Diabetes Association The Big Picture: Checking Your Blood Glucose
  6. National Library of Medicine The Beneficial Effects of a Paleolithic Diet on Type 2 Diabetes and Other Risk Factors for Cardiovascular Disease

About the Author

Ely Fornoville

Hi, I'm Ely Fornoville, and I am the founder of Diabetic Me. Being a type 1 diabetic since 1996, I developed a passion to help people learn more about diabetes. I write about diabetes and share stories from other diabetics around the world. I currently use a Medtronic Guardian 4 CGM and a MiniMed 780G insulin pump with Humalog insulin.

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