The target level for normal blood sugar varies for each person and is based on factors like age, health issues, and the type of treatment you use. Blood sugar can also change during the day, based on the time of your last meal.
Normal blood sugar levels are between 80 and 130 milligrams per deciliter (mg/dL) before a meal and less than 180 mg/dL two hours after a meal.
For many people with type 2 diabetes, low blood sugar is defined as a blood sugar level below 70 mg/dL. At this level, you’re likely to feel shaky or dizzy. You may also have a fast heartbeat, sweating, or headache. Knowing when low blood sugar occurs and how to fix it can prevent severe health effects and even save your life.
This article describes low blood sugar, what causes it, the symptoms, how it’s diagnosed, and treatment for people with type 2 diabetes.
Symptoms of Low Hypoglycemia Levels
Having low hypoglycemia levels affects everyone differently. It is common to have symptoms of low blood sugar when your level falls below 70 mg/dL. Your body reacts by releasing the stress hormone adrenaline (also known as epinephrine). The hormone promotes a “fight-or-flight” response that increases your blood circulation, heart rate, and breathing to prepare your body for danger.
Knowing how your body reacts to hypoglycemic effects can help you identify and treat the problem before it worsens.
Symptoms of low hypoglycemia levels happen quickly. Signs of low blood sugar in adults include the following reactions that can get worse as your levels continue to fall:
Shaky or jittery feeling Chills, sweating, or clammy feeling Hunger Fatigue or sleepiness Looking pale/loss of skin color (pallor) Lightheadedness or dizziness Confusion Fast heart rate Tingling or numbness in the cheeks, lips, or tongue Headache Inability to see or speak clearly Problems with coordination Loss of consciousness Seizure
When blood sugar levels fall and stay low for several hours while you are asleep, symptoms of hypoglycemia can include:
Nightmares or crying out Extreme sweating, causing damp pajamas or bedding Awakening with feelings of tiredness, irritability, or confusion
It’s important to note that if you have hypoglycemia frequently enough, you may no longer have symptoms. This is called hypoglycemia unawareness and it is a very dangerous condition.
When to Seek Immediate Medical Attention
Blood sugar levels that keep dropping without treatment can get very low. Severe hypoglycemia—defined as a blood sugar level below 55 mg/dL—can be treated with a glucagon injection or spray. The medication triggers a release of stored sugar from the liver, which raises blood sugar levels quickly.
However, severely low blood sugar is a serious condition. It can lead to seizures, coma, and even death if the levels remain low for an extended time.
Call 911 for immediate medical attention if:
You become unconscious and glucagon is not available. You require a second dose of glucagon. You remain confused despite having glucagon administered. Your blood sugar remains severely low 20 minutes after treatment or does not respond to your usual treatments. You have concerns about your severely low blood sugar.
How to Take a Blood Sugar Reading
Knowing how to take your blood sugar reading is important to managing your levels at home. The results can help you make informed decisions about your diet, exercise, and medication.
Your healthcare provider will give you instructions on the recommended timing and frequency of testing your blood sugar and your target ranges.
Here are a couple of ways you can check your blood sugar at home.
Blood Glucose Meter
A blood glucose meter (glucometer) is a small, portable machine used to measure blood sugar at the time the blood is checked. Here are the steps to follow to check your blood sugar with a glucometer:
Clean and dry your handsTurn on the glucose monitor and insert a test stripAdjust how deep the finger prick will go under your skinPrick the side of your finger with a small needle used to extract a drop of blood (lancet)Squeeze your finger until you have a drop big enough to put on the stripApply the blood to a test stripWipe away any remaining bloodSafely dispose of the lancet and stripKeep a record of your blood sugar readings so you can discuss them with your healthcare provider
Continuous Glucose Monitor
A continuous glucose monitor is a wearable device that continually tracks and provides blood sugar readings 24 hours a day. Most of these instruments provide a blood sugar reading every five minutes, though some take a reading as often as every 60 seconds.
There are two types of devices:
Real-time continuous glucose monitor: This device has a small wire sensor that is inserted under the skin on your arm or abdomen. A transmitter attaches to the sensor and there is a receiver that can be a separate device or attached to a sensor-augmented insulin pump. Some can send readings directly to your smartphone. These devices typically have an alarm to warn you that your blood sugar level is too low or too high. Intermittently scanned continuous glucose monitor: With this system, you scan the device when you want to read your blood sugar level by holding a transmitter up to the sensor.
While a continuous glucose monitor can reduce the number of finger sticks you have to do daily, you may have to check your results against a blood glucose monitor twice a day to ensure the accuracy of your continuous glucose monitoring system.
Causes
There are several factors that can cause low blood sugar in people with type 2 diabetes. For many people, hypoglycemia occurs even when they’re following a recommended diabetes treatment plan. Here are some factors that can lead to low blood sugar.
Low blood sugar (hypoglycemia): Below 70 mg/dLNormal blood sugar: 80-130 mg/dLHigh blood sugar (hyperglycemia): Above 140mg/dL
Hypoglycemia From Hyperglycemia Medications
Hypoglycemia occurs most often in people with type 2 diabetes who take insulin or oral medications that increase insulin production. Insulin lowers blood sugar levels when it is too high.
Taking too much insulin or other types of diabetes medications can allow your body to release more insulin than needed. Having excess insulin causes your cells to absorb too much sugar. As a result, there is not enough sugar in your blood.
During Sleep
More than 50% of severe hypoglycemic episodes occur during sleep. Called nocturnal hypoglycemia, it happens most often among people taking insulin. You increase your risk for hypoglycemia by skipping meals, exercising or drinking alcohol before bedtime, or not consuming enough carbohydrates before sleep.
Nightmares or calling out in your sleep can be symptoms of nocturnal hypoglycemia but many episodes go undetected—especially in people who sleep alone. Untreated nocturnal hypoglycemia can cause seizures, coma, and cardiovascular events that can affect a person’s quality of life.
Insufficient Carbohydrates
Your body makes glucose by breaking down the sugars and starches in the carbohydrates you eat. Glucose raises your blood sugar level when it enters your bloodstream. Without enough carbohydrates in your diet, your blood sugar levels can decline.
Missing Meals
You increase your risk of hypoglycemia if you miss a meal or eat later than usual while taking insulin or oral medications for diabetes. If this happens while you reduce your carb intake, you can develop low blood sugar from the combination of increased insulin and decreased fuel for blood glucose.
Exercise
Increasing exercise or another type of physical activity beyond normal can raise your risk of triggering a spike in insulin up to 24 hours or more after exercise, which can lower blood sugar. You can risk sudden hypoglycemia if you are already taking insulin or insulin-promoting medication. Checking your blood sugar level before exercise and monitoring insulin and carbohydrate intake are important for avoiding hypoglycemia.
Alcohol Consumption
Consuming alcohol while you are taking insulin or diabetes medications can cause hypoglycemia.
Your liver stabilizes glucose levels by storing carbs and releasing them into the bloodstream during fasting periods between meals and sleep. It also breaks down toxins like alcohol so the kidneys can flush them out.
For people with type 2 diabetes, the problem with drinking alcohol is that the liver cannot always do both of these jobs at the same time. Drinking alcohol may prevent your liver from maintaining your blood sugar in favor of metabolizing the alcohol.
Managing Hypoglycemia
Even with closely managing your blood sugar levels and following your diabetes treatment plan, it’s possible to develop hypoglycemia. Knowing what blood sugar level is too low and how to manage hypoglycemia can help you identify the symptoms, recognize low blood sugar levels, and treat the problem before it becomes a serious health issue.
Reactive hypoglycemia: Reactive hypoglycemia, also called postprandial hypoglycemia, occurs after eating—usually in people with pre-diabetes or who are at risk for diabetes. Fasting hypoglycemia: Fasting hypoglycemia occurs from not eating or allowing too much time between meals. Certain medicines or alcohol can increase your risk of this type of low blood sugar. Serious illnesses, pancreatic tumors, or low levels of certain hormones can also cause the condition.
15-15 Rule
The American Diabetes Association (ADA) advises people with diabetes to use the 15-15 rule to raise blood glucose levels below 70 mg/dL to between 55-69 mg/dL. The diabetes rule of 15 is as follows:
Consume 15 grams of fast-acting carbohydratesCheck your blood sugar after 15 minutesRepeat the process until your blood sugar increases to within your target rangeEat a nutritious snack or meal to prevent low blood sugar from recurring
Though you may want to eat more, overeating can increase your blood sugar levels too fast.
There are many ways to consume 15 grams of fast-acting carbohydrates. Some common items that meet this standard include:
Glucose gel tube (taken per instructions)Three to four glucose tablets (taken per instructions)4 ounces of regular soda or juice1 tablespoon of honey, sugar, or corn syrupServing size equal to 15 grams of hard candies, gumdrops, or jellybeans (check the product label)
Treating Extreme Low Blood Sugar
A blood sugar level that falls below 55 mg/dL is considered extremely low blood sugar and is an emergency. If your blood sugar goes this low, you may become unconscious or otherwise unable to act on your own. That’s why it’s important to make sure that your friends, coworkers, and family members know how to help you if it happens.
If you have extremely low blood sugar, you will be unable to eat or drink. The only way to stop falling blood sugar levels is to consume emergency glucagon through an injection or nasal spray. If you qualify for it, your healthcare provider can give you a prescription for an emergency glucagon kit to have on hand for emergencies.
If you are treated with an emergency injection of glucagon, you should return to consciousness within five to 15 minutes. When you wake up, consume a small piece of fruit, candy, or juice and recheck your blood sugar levels after 15 minutes.
Finding a Trustworthy Provider
Managing hypoglycemia with type 2 diabetes will likely involve a team of healthcare providers who can help you with the different aspects of your care. If you are searching for providers who specialize in type 2 diabetes, try the following strategies:
Contact a Certified Diabetes Care and Education Specialist (CDCES). A certified diabetes care and education specialist is a healthcare provider who has extensive training and experience that qualifies them to help people living with diabetes. You can find a local expert in a diabetes education program that’s recognized by the American Diabetes Association at diabetes. org/findaprogram or by calling 1-800-DIABETES (800-342-2383) to find a program in your community. A CDCES can provide valuable services to help you manage your condition. They might also be able to refer you to other diabetes healthcare professionals in your area. Check the Federation of State Medical Boards (FSMB) Physician Data Center website. You can verify the credentials and disciplinary history of physicians and physicians’ assistants based on data from state medical boards and other national and international licensing authorities. Ask your primary care provider to connect you with specialists. Certain providers such as endocrinologists, registered dietitians, and exercise professionals, provide care for people with diabetes. Your primary care provider might be able to refer you to one or more of these providers. Ask family members, friends, and coworkers for recommendations. The recommendation of a trusted friend or family member that’s based on their experiences can help you feel more comfortable about working with a new healthcare provider.
Type 2 Diabetes Hypoglycemia Resources
You can access a wide range of resources for managing hypoglycemia with type 2 diabetes through national diabetes organizations. The services offered include educational resources, diabetes news, directories of healthcare providers, peer and professional support, and information that can help you navigate the physical, emotional, and practical aspects of living with type 2 diabetes.
Consider reaching out to your primary care provider for help in the areas where you need it most. If their office cannot offer support, check with a local chapter of the American Diabetes Association or another diabetes support group. Search the website of the American Diabetes Association for resources where you can learn about the benefit of self-management and following a treatment plan.
Social media sites can also offer the benefit of input from others who have overcome the same barriers to self-management that you are dealing with. You can also try using smartphone apps to record your blood glucose data and remind you to take your medications.
Some of the leading national resources include:
Academy of Nutrition and Dietetics American Diabetes Association (ADA) American Heart Association (AHA) Association of Diabetes Care and Education Specialists (ADCES) Diabetes-Exercise. org International Diabetes Federation (IDF) National Institute of Diabetes and Digestive and Kidney Diseases
Check with your healthcare provider about diabetes resources in your area that is sponsored by local chapters of national diabetes organizations, libraries, healthcare centers, health departments, or other organizations.
Summary
Low blood sugar (hypoglycemia) is when your blood sugar level falls below normal levels. Having type 2 diabetes and taking insulin or medications that promote its release can increase your risk for low blood sugar. People with type 1 diabetes as well as people who do not have diabetes can also have low blood sugar.
Your normal blood sugar level is based on factors like your age, other health conditions, and the type of treatment you use. It can also vary during the day as you eat and the food is changed into glucose. Normal blood sugar levels are between 80 and 130 milligrams per deciliter (mg/dL) before a meal and less than 180 mg/dL two hours after a meal.
For many people with type 2 diabetes, low blood sugar is defined as 70 mg/dL. The effect can make you feel shaky or dizzy. You may also have a fast heartbeat, sweating, or headache. Learning how to know when you have low blood sugar and what to do can help you correct it early and avoid complications.
A Word From Verywell
It’s normal to feel frustrated if you have to monitor your blood sugar levels despite your efforts to follow your diabetes treatment plan. However, it’s important to understand that your efforts to identify and treat symptoms of hypoglycemia can affect your health and quality of life.
Untreated hypoglycemia that falls to extremely low levels carries the risk of seizures, a coma, or even death. Being prepared to act and fix low blood sugar levels quickly can help prevent these complications. Having the supplies that others will need to treat an extreme hypoglycemic event where you cannot care for yourself could protect even save your life.
