what is dangerously low blood sugar

Hypoglycemia is a condition where the concentration of glucose in the blood drops below what is needed. It is particularly common during diabetes treatment and can become a dangerous state that can be life-threatening. It is important to know what is considered dangerously low blood sugar levels and understand the appropriate response.

Understanding Hypoglycemia Levels

Blood glucose level is an indicator of the concentration of glucose, which is the body’s energy source. When this value falls below the normal range, various symptoms can appear. What level is considered low blood sugar, and what levels are particularly dangerous?

What level is considered low blood sugar?

Generally, a blood glucose level below 70 mg/dL is defined as hypoglycemia. This is a widely used standard based on diabetes treatment guidelines. However, the blood glucose level at which symptoms appear varies among individuals. For people who usually have high blood sugar or who experience frequent hypoglycemia, symptoms similar to hypoglycemia may occur even at blood glucose levels higher than 70 mg/dL.

What is the normal blood sugar range?

In healthy individuals, blood glucose levels are usually maintained within the range of 70 mg/dL to 140 mg/dL, regardless of meals. Fasting blood glucose (after at least 8 hours without food) is typically between 70 mg/dL and 100 mg/dL. After a meal, it temporarily rises but usually returns to below 140 mg/dL within 2 hours. Maintaining within this narrow range is the normal state.

Is 50 or 60 low blood sugar?

Yes, blood sugar levels of 50 mg/dL and 60 mg/dL are clearly low. These levels fall below the 70 mg/dL threshold and are classified as hypoglycemia. At these levels, various symptoms of hypoglycemia usually appear. Especially when the level drops below 50 mg/dL, glucose supply to the brain is significantly reduced, making it a dangerous level where severe symptoms like impaired consciousness are likely to occur.

At what point is low blood sugar an emergency?

When blood glucose levels fall below 54 mg/dL, it is considered severe hypoglycemia and requires particular attention. At this level, it is often difficult for individuals to treat themselves. Furthermore, if blood glucose continues to drop to extremely low values, such as below 30 mg/dL, the brain function cannot be maintained, potentially leading to coma or seizures. This is a very dangerous, life-threatening state.

Signs and Symptoms of Low Blood Sugar

The symptoms of hypoglycemia vary depending on how low the blood sugar drops and how quickly it falls. They range from mild initial symptoms to severe advanced symptoms. It is important not to miss the body’s warning signs.

How do you feel when your sugar is low?

Initial symptoms of hypoglycemia occur due to the stimulation of the autonomic nervous system. Typical examples include intense hunger, trembling hands and feet, cold sweats, palpitations, and paleness. These symptoms occur because the body secretes hormones like adrenaline in an attempt to raise blood sugar. If left untreated, symptoms due to insufficient glucose supply to the brain appear. These include dizziness, weakness, difficulty concentrating, drowsiness, yawning, visual disturbances such as blurred or double vision, headache, anxiety, and irritability.

type 2 diabetes, low blood sugar symptoms

Type 2 diabetes patients can also experience hypoglycemia, particularly when treated with oral glucose-lowering medications or insulin. Symptoms are similar to the basic ones, but in patients with long-standing diabetes or nerve damage, typical autonomic symptoms (like trembling or cold sweats) may not be noticeable. This is called “hypoglycemia unawareness” and is very dangerous. Blood sugar can drop to dangerous levels without symptoms being felt, potentially leading to sudden loss of consciousness. Therefore, regular blood glucose monitoring becomes even more crucial.

What are the signs of low blood sugar at night?

Hypoglycemia can also occur during sleep at night. Symptoms are often subtle or unnoticed, and individuals may only become aware in the morning. Signs may include profuse sweating during sleep, restless sleep, nightmares, or waking up with severe fatigue or headache. As with daytime hypoglycemia, there is a risk of hypoglycemia unawareness. Frequent nocturnal hypoglycemia can also negatively affect daytime blood sugar control and increase the risk of long-term complications.

Causes of Low Blood Sugar

Hypoglycemia primarily occurs as a side effect of diabetes treatment, but it can also happen in people without diabetes. Various factors contribute to a drop in blood sugar levels. Understanding the causes helps in more effective prevention and treatment.

What causes low blood sugar without diabetes?

Hypoglycemia can occur in people not using diabetes medications. This is called “non-diabetic hypoglycemia.” Causes are varied. For example, prolonged strenuous exercise, skipping meals, or excessive alcohol consumption can lead to it. Certain medical conditions, such as insulinoma (a tumor in the pancreas that secretes excessive insulin), severe liver disease, kidney disease, or dysfunction of the adrenal or pituitary glands, can also cause hypoglycemia. After gastric surgery or certain bariatric surgeries, “reactive hypoglycemia” can occur, where blood sugar rapidly rises after a meal, followed by an exaggerated insulin response leading to low blood sugar.

Can stress cause low blood sugar?

Directly, stress is rarely a primary cause of rapid blood sugar drops. However, stress can affect blood sugar control. The stress response typically involves the release of hormones (cortisol, adrenaline, etc.) that raise blood sugar, more often leading to hyperglycemia. However, changes in eating patterns due to stress (skipping meals, irregular eating) or excessive alcohol consumption for stress relief can indirectly lead to hypoglycemia. Also, stress symptoms (like trembling or palpitations) can be similar to those of hypoglycemia, leading to confusion.

Medications and Alcohol

Certain medications carry a risk of causing hypoglycemia. Besides diabetes medications, some antibiotics, antimalarial drugs, and non-selective beta-blockers are known examples. If you are using these medications, be aware of the symptoms of hypoglycemia. Alcohol consumption can also be a significant cause of hypoglycemia. Especially when drinking alcohol on an empty stomach or with insufficient food, the liver’s glucose production is suppressed, making blood sugar more likely to drop. Alcohol also impairs judgment, making it harder to notice early symptoms of hypoglycemia and increasing the risk of severe episodes. For diabetes patients using insulin or oral medications, the risk of hypoglycemia from alcohol is even higher.

Emergency Treatment and Response

Hypoglycemia is a race against time. When symptoms are felt, it is crucial to act quickly and appropriately. This is especially true if blood sugar is dropping rapidly or symptoms are severe, requiring immediate action.

What to do when blood sugar is low

If you feel symptoms of hypoglycemia or confirm a blood glucose level below 70 mg/dL with a test, consume glucose immediately. This is the basic treatment for hypoglycemia. The “15-15 rule” is generally recommended. This method involves consuming 15 grams of glucose, waiting 15 minutes, and then retesting blood sugar. If blood sugar is still low, consume another 15 grams of glucose and wait another 15 minutes before testing again. Repeat this process until blood sugar recovers. Glucose usually takes effect relatively quickly. Even if symptoms improve, if the next meal is still some time away, consume a small amount of carbohydrates that raise blood sugar slowly, such as biscuits or bread. This should be beneficial.

What to eat when blood sugar is low

To raise blood sugar quickly, choose foods containing rapidly absorbed carbohydrates. The most recommended is glucose itself. Effective glucose-containing foods include glucose tablets, juice (100% fruit juice or sweetened), sugary sodas (not diet versions), and sugar. Foods like chocolate or ice cream contain fat, which slows down sugar absorption, making them unsuitable for emergency treatment of hypoglycemia.

What is the best thing to drink when your blood sugar is low?

For rapidly raising blood sugar, 100% fruit juice or sugary soft drinks are ideal. They contain a high amount of sugar and are quickly absorbed from the gastrointestinal tract, effectively raising blood sugar. For example, about 150ml of orange or apple juice can provide about 15 grams of glucose. Sports drinks also contain sugar, but juice is generally more effective for treating hypoglycemia due to its higher sugar concentration. Adding sugar to coffee or tea is also an option, but consider the potential strain on the heart due to caffeine. Choose sugary drinks specifically for the purpose of raising blood sugar, not just for hydration.

How long does it take to recover from low blood sugar?

After consuming glucose, blood sugar typically begins to rise within 10 to 20 minutes, and symptoms start to improve. The 15-15 rule mentioned earlier is based on this recovery time. However, it may take a bit longer for symptoms to fully disappear and for you to feel completely back to normal. Recovery tends to take more time if the hypoglycemia was severe or if you experience hypoglycemia unawareness. Also, depending on the type of diabetes medication being used (especially long-acting insulin or oral medications), blood sugar may drop again even after initial recovery, so caution is needed.

Severe Hypoglycemia Risks

Severe hypoglycemia, if not treated promptly, can lead to very dangerous conditions. It not only causes uncomfortable symptoms but also poses life-threatening risks and long-term health effects that cannot be ignored.

What is a fatal low blood sugar level?

There is no definitive “universally fatal level” of blood sugar. Many factors are involved, including an individual’s physical condition, age, underlying diseases, and the duration of low blood sugar. However, if extremely low blood sugar levels, such as below 20 mg/dL, persist for a long time, the brain’s energy supply is cut off, brain function ceases, and it can lead to death. The risk of a fatal outcome is particularly high if severe hypoglycemia occurs during the night or in a situation where no one is aware, leading to delayed discovery.

Which low blood sugar level puts you in a coma?

Generally, when blood sugar drops below 50 mg/dL, brain function starts to be affected, which can cause confusion or unusual behavior. When blood sugar drops further, typically below 30 mg/dL, the brain’s function cannot be maintained, making loss of consciousness (hypoglycemic coma) and generalized seizures very likely. However, there is individual variation; some people may go into a coma at higher blood sugar levels depending on their usual blood sugar control and the speed of the drop, while others may remain conscious at quite low blood sugar levels.

Can you die from low blood sugar in your sleep?

Yes, severe hypoglycemia during sleep can increase the risk of death. During sleep, it is difficult to notice the early symptoms of hypoglycemia, leading to delayed treatment as symptoms worsen. For patients with hypoglycemia unawareness, noticing symptoms is even harder than during the day, making nocturnal hypoglycemia particularly dangerous. If the brain is deprived of glucose for a prolonged period, recovery can become difficult, and in the worst case, it can lead to death. It is crucial to discuss measures to prevent nocturnal hypoglycemia (such as checking blood sugar before bed, and having a snack if necessary) with a healthcare professional.

What are the long-term effects of low blood sugar?

Repeated or severe episodes of hypoglycemia can have various long-term effects. The most significant concern is an increased susceptibility to hypoglycemia unawareness. This is a state where the body becomes accustomed to low blood sugar and the warning signs (like trembling and cold sweats) become less noticeable. Hypoglycemia unawareness dramatically increases the risk of severe hypoglycemia. Furthermore, severe hypoglycemia has been suggested to increase the risk of cardiovascular events. Brain damage is also a concern, but this is rare and usually resolves with appropriate resuscitation. However, recurrent hypoglycemia has been suggested to potentially affect cognitive function.

Preventing Dangerous Lows

Preventing hypoglycemia, especially dangerous severe hypoglycemia, is extremely important in diabetes management. Daily lifestyle habits, medication management, and understanding your body’s condition are key to prevention.

Low blood sugar levels chart and monitoring

Regular blood glucose monitoring is essential for early detection and prevention of hypoglycemia. Check your blood sugar at the frequency and times instructed by your doctor. Creating a blood glucose level chart and understanding your blood sugar patterns can also be helpful. Recording whether you tend to experience hypoglycemia at specific times (e.g., after exercise, before meals, at night, early morning) makes it easier to implement preventive measures. Using a Continuous Glucose Monitor (CGM) allows more frequent monitoring of blood sugar fluctuations and can alert you in real-time about impending hypoglycemia, making it very effective for prevention.

How to prevent low blood sugar at night?

Several measures can help prevent nocturnal hypoglycemia. First, always check your blood sugar before going to bed. If your blood sugar is low, consider having a light snack (for example, one containing slowly absorbed carbohydrates), following the guidance of your doctor or dietitian. You may also need to review the dose and timing of your insulin injections or oral glucose-lowering medications, especially if you exercise in the evening. Alcohol consumption increases the risk of nocturnal hypoglycemia, so avoid drinking alcohol before bed or limit it to a small amount. It is important to discuss these measures with your primary physician and receive advice tailored to your individual situation.

Summary

Hypoglycemia, especially at dangerous levels, is one of the most critical complications to watch for in patients undergoing diabetes treatment. Blood sugar below 70 mg/dL is considered hypoglycemia, and below 54 mg/dL increases the risk of severe hypoglycemia. Symptoms range from early signs like trembling and cold sweats to impaired consciousness and coma. Causes are diverse, including incorrect medication dosage or timing, insufficient food intake, increased exercise, and alcohol. When symptoms appear, it is crucial to perform immediate first aid by consuming glucose (using the 15-15 rule, etc.) to restore blood sugar levels. Severe hypoglycemia carries risks of brain damage and death, making daily blood glucose monitoring and strict lifestyle management essential for prevention. Awareness of hypoglycemia unawareness and nocturnal hypoglycemia is also important.

If you have any concerns or questions about hypoglycemia, always consult with a doctor or diabetes specialist healthcare professional. With proper knowledge and preparation, you can reduce the risk of dangerous hypoglycemia and manage your diabetes safely.

【Disclaimer】

This article is for general information purposes only and does not constitute medical advice. For diagnosis or treatment regarding individual medical conditions, please consult a qualified healthcare professional. We do not assume any responsibility for any damage caused by actions taken based on the information in this article.