Dangers of Uncontrolled Blood Sugar

If your blood sugar is too high for too long, it can cause serious health problems. It’s something to be careful of whether you have diabetes or not.

How high is too high? Your doctor will tell you what your target range should be and what to do if your levels aren’t in that range. If you have diabetes, you'll need to check your blood sugar, also called glucose, to know if it’s too high, too low, or meets your goal.

The problems that high blood sugar can cause happen over time. The sooner you get your levels back in line, the better.

What High Blood Sugar Feels Like

The symptoms can include:

  • Feeling thirstier than usual
  • Blurred vision
  • Having to pee more often
  • Feeling hungrier than normal
  • Numb or tingling feet

You might also feel more tired than usual, get infections on your skin, or notice that cuts and sores take a long time to heal.

Tell your doctor if you have any of these symptoms.

Complications

High glucose levels can affect you from head to toe. If they're out of control for a long time, you could have some or all of the following:

  • Heart disease or heart attack
  • Stroke
  • Kidney damage
  • Nerve damage
  • Eye damage
  • Skin problems

When to Call Your Doctor

Pick up the phone if your blood sugar is high and you have any of these symptoms:

  • Trouble breathing
  • Vomiting
  • High levels of ketones in your urine
  • Extreme thirst or a very dry mouth
  • Having to pee too often
  • Dry or flushed skin
  • Breath that smells like fruit
  • Confusion

These are symptoms of diabetic ketoacidosis (DKA). Your body burns glucose for energy. When your cells don’t get enough of it, they burn fat. That produces chemicals called ketones. When these build up, your blood becomes more acid-like. This can be life-threatening if it’s not treated.

Hyperosmolar Hyperglycemic Nonketotic Syndrome (HHNS)

This mostly affects elderly people. As glucose builds up in your blood, your body tries to get rid of it through your urine.

At first, you pee a lot. Over time, you pee less, but when you do, it’s very dark. This condition can lead to dehydration, coma, and death.

Get medical help right away if you have any of these warning signs:

  • Blood sugar level over 600 mg/dL
  • Extreme thirst that may later go away
  • Warm, dry skin that doesn’t sweat
  • Fever over 101 F
  • Sleepiness or confusion
  • Weakness on one side of your body
  • Vision loss
  • Hallucinations

You can avoid many of these problems by keeping your blood sugar under control. Follow your doctor’s advice about diet and exercise, take your medicine, keep up with your doctor visits, and check your levels often.

WebMD Medical Reference Reviewed by Brunilda Nazario, MD on December 10, 2018

Sources

SOURCES:

Joslin Diabetes Center: “High Blood Glucose: What It Means and How to Treat It.”

Gov.UK: “Hyperglycaemia (high blood sugar).”

Cleveland Clinic: “Hyperglycemia (High Blood Sugar).”

EndocrineWeb: “Hyperglycemia: When Your Blood Glucose Level Goes Too High.”

American Diabetes Association: “DKA (Ketoacidosis) & Ketones.”

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