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Hyperglycemia is when the amount of sugar, or glucose, in your blood is too high. High blood sugar can happen if you have diabetes or if you don't have diabetes. It may be an emergency.

What are the causes?

If you have diabetes, high blood sugar may be caused by:

1. Medicines that increase blood sugar.
2. Not giving yourself enough insulin (if you take it).
3. Being less active than normal.
4. Eating more than planned.
5. Illness, an injury, or an infection.
6. Having surgery.
7. Stress.

If you don't have diabetes, high blood sugar may be caused by:

1. Certain medicines, such as steroids or thiazide diuretics.
2. Stress.
3. A bad illness or infection.
4. Having surgery.
5. Diseases of the pancreas.

What increases the risk?

You're more likely to have high blood sugar if:

a. Someone in your family has diabetes.

b. You're overweight.

c. You aren't active.

d. You have or have had:

1. Prediabetes.
2. Diabetes when pregnant.
3. Polycystic ovarian syndrome (PCOS).

What are the signs or symptoms?

High blood sugar may not cause symptoms. If you do have symptoms, they may include:

1. Feeling more thirsty than normal.
2. Needing to pee more often than normal.
3. Hunger.
4. Feeling very tired.
5. Blurry eyesight.

You may have other symptoms if your high blood sugar isn't treated. These may include:

1. Pain in your belly.
2. A headache.
3. Weakness.
4. Weight loss that's not planned.
5. A tingling or numb feeling in your hands or feet.
6. Cuts or bruises that heal slowly.

How is this diagnosed?

High blood sugar is diagnosed with a blood test. This test tells you how much sugar is in your blood. It's done while you're having symptoms.

Your health care provider may also do a physical exam, look at your medical history, and do more blood tests. These tests may include:

1. A fasting blood glucose (FBG) test. You can't eat for at least 8 hours before this test.
2. An A1C test.
3. A glucose tolerance test.

How is this treated?

Treatment may include:

a. Taking medicine to control your blood sugar levels.

b. Changing your medicine or how much you take if you take insulin or other diabetes medicines.

c. Checking your blood sugar more often.

d. Making changes to your daily life. These may include:

1. Being more active.
2. Eating healthier foods.
3. Losing weight.

e. Treating an illness or infection.

f. Stopping or taking less steroids.

If your high blood sugar stays high, you may need to be treated in the hospital.

Follow these instructions at home:

If you have diabetes:

a. Know the symptoms of high blood sugar.

b. Follow your diabetes care plan. Make sure you:

1. Take insulin and medicines as told.
2. Check your blood sugar as often as told.
3. Eat on time. Do not skip meals.
4. Check your blood sugar before and after you exercise. If you exercise longer or harder than normal, check your blood sugar more often.
5. Follow your sick day plan when you can't eat or drink like normal. Make this plan ahead of time with your provider.

c. Share your diabetes care plan with:

1. Your work or school.
2. The people you live with.

d. Wear an alert bracelet or carry a card that says you have diabetes.

General instructions

a. Take medicines only as told by your provider.

b. Drink enough fluid to keep your pee (urine) pale yellow. Make sure you drink enough when you:

1. Exercise.
2. Get sick.
3. Are in hot places.

c. If you drink alcohol:

1. Limit how much you have to:
2. 0–1 drink a day if you're female.
3. 0–2 drinks a day if you're male.
4. Know how much alcohol is in your drink. In the U.S., one drink is one 12 oz bottle of beer (355 mL), one 5 oz glass of wine (148 mL), or one 1½ oz glass of hard liquor (44 mL).

d. Manage stress. If you need help with this, ask your provider.

e. Exercise as told. Try to stay at a healthy weight.

f. Keep all follow-up visits. Your provider will want to make sure your high blood sugar is treated.

Contact a health care provider if:

a. You have diabetes and have trouble keeping your blood sugar in the right range.

b. Your blood sugar is at or above 240 mg/dL (13.3 mmol/L) for 2 days in a row.

c. You have high blood sugar often.

d. You have signs of illness, such as:

1. Nausea or vomiting.
2. A headache.
3. A fever.

e. You can't stop vomiting.

Get help right away if:

1. Your blood sugar monitor reads "high" even when you're taking insulin.
2. You have trouble breathing.

These symptoms may be an emergency.

1. Do not wait to see if the symptoms will go away.
2. Do not drive yourself to the hospital.

This information is not intended to replace advice given to you by your health care provider. Make sure you discuss any questions you have with your health care provider.