You can get seizures because of high blood sugar. Diabetes or other health conditions may be the cause. A doctor can use insulin to lower your glucose levels, and dehydration treatment to manage these seizures.

Seizures can occur if you experience very high levels of blood sugar (hyperglycemia).

Diabetes is one potential cause of hyperglycemia, and when seizures occur as a result of this condition, they’re considered dangerous. Seizures related to hyperglycemia may also happen after surgery or because of medications. Treatments often involve lowering your glucose level and addressing dehydration.

This article will address how hyperglycemia causes seizures and what you can discuss with your healthcare team when treating both hyperglycemia and seizures.

Hyperglycemia can be defined as blood sugar levels higher than 125 mg/dL after not eating for at least 6 hours. This is higher than the normal 70–100 mg/dL level that people with diabetes typically experience. When two or more fasting blood sugar checks are 126 mg/dL or higher, that person may have diabetes.

Older research indicates that approximately 25% of individuals with diabetes will have some type of seizure, but seizures may occur in any individual with extremely high blood sugar. This is because the high amount of blood sugars can cause neurons in the brain to become overstimulated.

Hyperglycemia leads to a decrease in levels of gamma-aminobutyric acid (GABA), making a person more prone to seizures. But more research into the connection between hyperglycemia and seizures is still needed.

There are two types of hyperglycemia known to cause seizures: nonketotic hyperglycemia (NKH) and ketotic hyperglycemia.

Nonketotic hyperglycemia (NKH)

NKH is also sometimes called diabetic hyperglycemic hyperosmolar syndrome (HHS).

In NKH/HHS, the kidneys will typically first compensate for high blood sugar levels by trying to excrete excess glucose in urine. This can cause the body to become dehydrated due to the extra water loss. If the kidneys do not have sufficient fluid to continue creating urine, they won’t be able to flush out the extra glucose, and it will build up in the bloodstream.

An individual’s blood may also become more concentrated if there is not sufficient water impacting the concentration of nutrients and cause water to be drawn out of other organs, including the brain.

NKH can have complications outside of seizures, including nonketotic hyperglycemic hemichorea where individuals experience involuntary movements, and nonketotic hyperosmolar coma where consciousness is lost.

Ketotic hyperglycemia

When an individual experiences ketotic hyperglycemia, their body starts to burn fat, because they can’t use the elevated blood glucose for fuel. As fat is burned, ketones are released into the bloodstream. When this occurs too quickly or in too great of quantities, it can turn an individual’s blood acidic.

Diabetic ketoacidosis (DKA) is a condition where ketones build up to dangerous levels in the body. Those can lead to seizures, coma, and even death.

Difference between low and high blood sugar seizures

Seizures may occur from both low and high blood sugar spikes. If a seizure is occurring from low blood sugar, it’s important to not inject insulin as this can make blood sugar levels drop even further. Instead, glucagon should be used to increase the amount of glucose in the bloodstream.

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If you have risk factors for high blood sugar or a history of hyperglycemia, it’s important to test your blood sugar levels frequently. Intervening before blood sugars reach levels that are dangerously high is the best way to prevent seizures from hyperglycemia.

If blood sugars spike suddenly and a seizure occurs, it’s important to get immediate medical attention. Treatment for hyperglycemic seizures typically requires insulin administration to reduce blood sugar levels. It’s important that this is done with medical supervision so it’s not done too fast, which could cause additional complications.

In addition to administering insulin, doctors may use IV fluids to correct fluid deficits and reduce insulin resistance. Potassium replacement is also generally necessary to help the body return to a state of equilibrium.

What blood sugar level causes seizures?

Non-ketotic hyperglycemia (NKH) is associated with a blood sugar level greater than 200 mg/dL. On the other end of the spectrum, older research from 2014 found generalized tonic-clonic seizures in several individuals whose glucose fell below 36 mg/dL. Focal seizures were noted in several individuals in the study with glucose levels up to 59 mh/dL.

Are hyperglycemic seizures dangerous?

Hyperglycemic seizures are potentially fatal and should be taken seriously. If you have risk factors for hyperglycemia, it’s important to talk with your doctor about what steps you can take to reduce the risk of a seizure from a blood sugar spike.

Can diabetes alert dogs prevent a hyperglycemic seizure?

Diabetes alert dogs are trained to notify their companions of blood sugar spikes or drops before these glucose changes are otherwise noticed. In the first groundbreaking study of its kind about diabetes alert dog reliability, researchers found that while they’re not 100% accurate, diabetes alert dogs are capable of notifying their owners of important blood sugar changes.

One potential risk of hyperglycemia is having a seizure. Seizures related to hyperglycemia are potentially fatal, and it’s important to seek medical assistance right away if one occurs. To treat a seizure from hyperglycemia, doctors may administer insulin, IV fluids, potassium, or even antiseizure medications to help the body stabilize.

If you have diabetes or another health condition that increases your risk of hyperglycemia, it’s important to talk with your doctor about ways to monitor and control blood sugar levels to prevent seizures and other serious health complications.