Have low blood sugar without symptoms? You may need to check your blood sugar more often.
Blood sugar levels change often during the day. When they drop below 70 mg/dL, this is called having low blood sugar. At this level, you need to take action to bring it back up. Low blood sugar is especially common in people with type 1 diabetes.
Knowing how to identify low blood sugar is important because it can be dangerous if left untreated. Read more about what causes low blood sugar and common symptoms.
Causes of Low Blood Sugar
There are many reasons why you may have low blood sugar, including:
- Taking too much insulin.
- Not eating enough carbs for how much insulin you take.
- Timing of when you take your insulin.
- The amount and timing of physical activity.
- Drinking alcohol.
- How much fat, protein, and fiber are in your meal.
- Hot and humid weather.
- Unexpected changes in your schedule.
- Spending time at a high altitude.
- Going through puberty.
- Menstruation.
Symptoms of Low Blood Sugar
How you react to low blood sugar may not be the same as how someone else with low blood sugar reacts. It’s important to know your signs. Common symptoms may include:
- Fast heartbeat
- Shaking
- Sweating
- Nervousness or anxiety
- Irritability or confusion
- Dizziness
- Hunger
If you’ve had low blood sugar without feeling or noticing symptoms (hypoglycemia unawareness), you may need to check your blood sugar more often to see if it’s low and treat it. Driving with low blood sugar can be dangerous, so be sure to check your blood sugar before you get behind the wheel.
You may not have any symptoms when your blood sugar is low (hypoglycemia unawareness). If you don’t have symptoms, it will be harder to treat your low blood sugar early. This increases your risk of having severe lows and can be dangerous. This is more likely to happen if you:
- Have had diabetes for more than 5-10 years.
- Frequently have low blood sugar.
- Take certain medicines, such as beta blockers for high blood pressure.
If you meet one or more of the above and you have hypoglycemia unawareness, you may need to check your blood sugar more often to see if it’s low. This is very important to do before driving or being physically active.
Types of Low Blood Sugar
Nighttime low blood sugar
While low blood sugar can happen at any time during the day, some people may experience low blood sugar while they sleep. Reasons this may happen include:
- Having an active day.
- Being physically active close to bedtime.
- Taking too much insulin.
- Drinking alcohol at night.
Eating regular meals and not skipping them can help you avoid nighttime low blood sugar. Eating when you drink alcohol can also help. If you think you’re at risk for low blood sugar overnight, have a snack before bed.
You may wake up when you have low blood sugar, but you shouldn’t rely on that. A continuous glucose monitor (CGM) can alert you with an alarm if your blood sugar gets low while you’re sleeping.
Severe low blood sugar
As your low blood sugar gets worse, you may experience more serious symptoms, including:
- Feeling weak.
- Having difficulty walking or seeing clearly.
- Acting strange or feeling confused.
- Having seizures.
Severe low blood sugar is below 54 mg/dL. Blood sugar this low may make you faint (pass out). Often, you’ll need someone to help you treat severe low blood sugar.
People with diabetes may experience low blood sugar as often as once or twice a week, even when managing their blood sugar closely. Knowing how to identify and treat it is important for your health. Learn how to treat low blood sugar.
Hypoglycemia is a condition caused by low blood glucose (blood sugar) levels. Glucose is the main way your body gets energy. The condition is most common in people with diabetes who have issues with medicine, food, or
exercise. But sometimes people who don't have diabetes can also get low blood glucose. There are two kinds of nondiabetic hypoglycemia: Most people feel symptoms of hypoglycemia when their blood sugar is 70 milligrams per deciliter (mg/dL) or lower. The symptoms may be different, depending on how low your blood sugar goes. They usually include: As hypoglycemia gets worse, symptoms might include: Diabetes drugs: Ask your doctor if any of your medicines can
cause low blood sugar. Insulin treatment can cause low blood sugar, and so can a type of diabetes medication called sulfonylureas.
Commonly used sulfonylureas include: Older, less common sulfonylureas tend to cause low blood sugar more often than newer ones. Examples
of older drugs include: You can also get low blood sugar if you drink alcohol or take allopurinol (Zyloprim), probenecid (Probalan), or warfarin (Coumadin) with diabetes medications. You shouldn't get hypoglycemia if you take alpha-glucosidase inhibitors, biguanides (such as
metformin), and thiazolidinediones alone, but it can happen when you take them with sulfonylureas or insulin. Your diet: You can get low blood sugar if you take too much insulin for the amount of carbohydrates you eat or
drink. For instance, it can happen: Don't skip meals if you have diabetes, particularly if you're taking diabetes medications.What is Hypoglycemia?
Symptoms of Hypoglycemia
What Causes Hypoglycemia in People With Diabetes?
Reactive hypoglycemia comes from having too much insulin in your blood. It usually happens within a few hours after you eat. Other possible causes include: Fasting hypoglycemia can have several causes: To diagnose nondiabetic hypoglycemia, your doctor will do a physical exam and ask
questions about any medicines you take. They’ll want to know all about your health and any history of diseases or stomach surgery. They’ll check your blood glucose level, especially when you are having symptoms. They’ll also check to see if you feel better when your sugar goes back to a normal level. If your doctor suspects hypoglycemia, you may have to
fast until you start to have symptoms. They’ll test your blood glucose level at different times throughout the fast. To check for reactive hypoglycemia, you may have to take a test called a mixed-meal tolerance test (MMTT). For this, you take a special drink that raises your blood glucose. The doctor will check your blood glucose levels over the next few hours. If you have diabetes,
check your blood sugar. If it’s below your target level or below 70, eat or drink 15 to 20 grams of carbohydrates. You can take juice, hard candy, or glucose tablets. This will usually help your symptoms go away. Check your blood sugar again in 15 minutes and treat every 15 minutes if levels are still low. Call 911 if you don’t feel well or if you
can’t get your blood sugar back up.What Causes Reactive Hypoglycemia?
What Causes Fasting Hypoglycemia?
Hypoglycemia Tests and Diagnosis
Hypoglycemia Treatment
If you don’t have diabetes: For a long-term solution, how you treat hypoglycemia depends on what's causing it. If a medicine triggers your low blood sugar, you may need to change it. If a tumor is to blame, you may need surgery.
For a quick fix, you can eat or drink 15 grams of carbohydrates, in the form of juice, glucose tablets, or hard candy. In the case of severe hypoglycemia, you may need a glucagon injection or intravenous glucose. The FDa has approved three medications for treating very low blood sugar:
- Baqsimi - taken as a nasal powder
- Dasiglucagon (Zegalogue) - taken by injection
- Gvoke - taken through injection
If you have diabetes, you can make some more easy changes to help keep your blood sugar steady: If you don’t have diabetes, ask your doctor if you need to adjust what you eat or how much you exercise. Diet changes like these might
help: Work with your doctor to figure out anything else that may be causing your symptoms. Hypoglycemia
may make you pass out. If so, you'll need someone to give you a glucagon shot. Glucagon is a prescription medicine that raises blood sugar. You may need it if you have severe hypoglycemia. It's important that your family members and friends know how to give the shot if you have a reaction to low blood sugar. If you see someone having a severe hypoglycemic reaction, call 911
or take them to the nearest hospital for treatment. Don’t try to give an unconscious person food, fluids, or insulin, as they may choke. It's dangerous. If you're driving and you have hypoglycemia symptoms, pull off the road, check your blood sugar, and eat a sugary food. Wait at least 15 minutes, check your blood sugar, and repeat these steps if needed. Eat a
protein and carbohydrate source (such as peanut butter crackers or cheese and crackers) before you drive on. Be prepared. Keep a sugar
source, such as glucose tablets, in your car at all times for emergencies.Hypoglycemia Prevention
If You Pass Out
Don’t Drive When You Have Low Blood Sugar