The quickest way to lower your blood sugar is to take fast-acting insulin. Exercising is another fast, effective way. However, in severe cases, you should go to the hospital.

High blood sugar levels are known as hyperglycemia or high blood glucose. This can result in diabetic ketoacidosis (DKA), when insulin levels are low. it is a medical emergency. DKA typically occurs in type 1 diabetes.

Symptoms of DKA include:

If you aren’t sure what to do, call your doctor for instructions on administering a dose of insulin and for advice about whether to go to the emergency room.

This article looks at ways to lower your blood sugar quickly when to go to the emergency room or see a doctor, and tips for managing high blood sugar.

When treated early, you can bring high blood sugar levels down and prevent complications, including DKA.

Some sources suggest that drinking water or eating a high protein snack can quickly lower your blood sugar levels, though there isn’t enough research to support this.

If you have high blood sugar and need to lower it fast, try the following methods:

Take your insulin as prescribed

High blood sugar occurs when your body has too little insulin, or your body can’t use insulin properly. Administering insulin can bring your blood sugar levels down.

Talk to your doctor about how much rapid-acting insulin you should administer when your blood sugar is high.

You may want to check your blood sugar a minimum of 30 minutes after taking insulin to make sure your blood sugar is going down and that it’s not dropping too low.

In these instances, you should not administer more correction insulin until at least 3 hours later to prevent insulin stacking and hypoglycemia.


Exercise is a fast and effective way to lower your blood sugar levels. Exercise can lower your blood sugar for 24 hours or more. This is because it makes your body more sensitive to insulin.

Physical activity causes the body to demand glucose for energy. As a result, the cells deliver glucose to the muscles and blood sugar levels usually drop.

Importantly, if your blood sugar is above 240 mg/dl, you should check your urine for ketones. If ketones are present, do not exercise because this can make your blood sugar rise even higher.

While exercise is an effective way to lower your blood sugar throughout the day, some exercises — particularly short bursts of strenuous activity — can briefly increase blood sugar levels.

This is because strenuous activity activates the body’s stress response, causing a release of glucagon to power the muscles.

According to the University of Michigan, blood sugar levels of 300 mg/dL or more can be dangerous. They recommend calling a doctor if you have two readings in a row of 300 or more.

Call your doctor if you’re worried about any symptoms of high blood sugar. They can offer advice and reassurance.

See your doctor if you have consistently high blood sugar levels. Symptoms of this include:

  • consistently high blood sugar readings
  • frequent urination
  • increased thirst
  • high levels of sugar in urine

Ask your doctor how often to check your blood sugar and your ideal blood sugar levels.

High blood sugar can be very concerning because your body can start burning fat for energy instead of blood glucose.

This can cause DKA, which is a medical emergency and can be fatal if left untreated.

Symptoms that can indicate you should go to the emergency room include:

DKA is a serious complication of type 1 diabetes. It’s rare in people with type 2 diabetes, but can occur.

When to call 911

If you or someone around you is experiencing any of the above symptoms in relation to diabetes, call 911 or visit the nearest emergency room. Prompt treatment can enhance outcomes.

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Checking your blood sugar and then treating hyperglycemia early will help prevent any complications.

Health problems can arise when someone has high blood sugar regularly and without treatment.

Examples of complications include:

  • nerve damage, called diabetic neuropathy, that may affect sensations in the feet and hands
  • diabetic retinopathy, or damage to the blood vessels in the eyes that affects vision
  • increased risks for kidney problems
  • increased risks for heart problems

Taking steps to keep your blood sugar at target levels can help to minimize the likelihood that these complications will occur.

Find several tips for avoiding blood sugar spikes here.

Here are some general guidelines for blood sugar ranges:

Blood sugarWhat to know
70 mg/dL or lowerHypoglycemia, or low blood sugar. Eat a snack to raise blood sugar (e.g. 1/2 cup fruit juice, 1 tbsp. honey, or 2 tbsp. raisins).
80–130 mg/dLIdeal preprandial range (before a meal).
180 mg/dL or lowerIdeal postprandial range (1–2 hours after beginning a meal).
240 mg/dL or higherCheck your urine for ketones. Call your doctor if you find moderate amounts of ketones after more than one test.

Read more about blood sugar monitoring here.

Most people can manage their diabetes in a way that stops their blood sugar levels from ever getting too high. The following tips can help:

Is blood glucose of 170 hyperglycemia?

To be diagnosed with hyperglycemia, your blood sugar needs to be higher than 125 mg/dL while fasting and higher than 180 mg/dL 2 hours after a meal. This means that 170 mg/dL could be considered hyperglycemia if it occurs while you fast.

Is 140 a hyperglycemia?

140 mg/dL could also mean hyperglycemia if your blood sugar is at this level while you fast.

What should I do if my blood sugar is 250?

If your blood sugar is at 250 mg/dL you should check your urine for ketones, and call your doctor if you find some in more than one test. You can buy an over-the-counter urine test kit at your local drugstore.

If you’re experiencing symptoms such as high blood sugar with vomiting and extreme thirst, go to the emergency room. Diabetic Ketoacidosis requires immediate medical treatment.

Administering insulin and exercising are two of the most common ways to get blood sugar levels down.

However, if someone has ketones in their urine or symptoms of excessively high blood sugar, they may need to go to the emergency room.