Diabetes can cause your blood sugar to be too high or too low. This can lead to kidney disease, nerve damage, and conditions that affect your skin, eyes, and feet.

Diabetes is a lifelong condition that requires ongoing attention. Without proper management, it can lead to several potentially severe complications.

If you have diabetes, it’s important to routinely monitor your blood sugar. No matter how careful you may be, it’s still possible that a problem might arise.

This article details the different complications that can occur in diabetes.

There are two types of complications you may experience: acute and chronic.

Acute complications require emergency care. Hypoglycemia (low blood sugar) and ketoacidosis (the buildup of acid in your blood as a result of high blood sugar) are examples of acute complications.

If left untreated, these conditions can lead to:

Without proper management, diabetes can also lead to chronic complications.

Diabetes causes high blood sugar. Over time and without proper treatment, this can damage various organs, including your:

Unmanaged diabetes can also cause nerve damage.

People with diabetes can experience sudden drops in their blood sugar. Skipping a meal or taking too much of a medication that increases insulin levels in your body can commonly cause this. Symptoms can include:

If your blood sugar gets too low, you may experience fainting, seizures, or coma.

Learn more about hypoglycemia.

This complication of diabetes occurs when your body cannot use sugar, or glucose, as a fuel source because your body has no insulin or not enough insulin. Ketoacidosis is most common in type 1 diabetes.

If your cells do not get enough energy, your body begins to break down fat. Potentially toxic acids called ketone bodies, which are byproducts of fat breakdown, then build up in your body. This can lead to:

Learn more about diabetic ketoacidosis.

Diabetes can damage blood vessels in your eyes and cause various eye conditions, such as the following:


Cataracts are 2 to 5 times more likely to develop in people with diabetes. Cataracts cause the eye’s clear lens to become cloudy, blocking light from getting in. Sunglasses and anti-glare lenses can often help treat mild cataracts. Severe cataracts may require a lens implant.

Learn more about cataracts.


This is when pressure builds up in your eye and restricts blood flow to your retina and optic nerve. Glaucoma causes gradual loss of vision. Compared to people without diabetes, people with diabetes are twice as likely to develop the most common type of glaucoma.

Learn the causes, types, and treatments of glaucoma.

Diabetic retinopathy

Diabetic retinopathy is a category that includes any problems with the retina that are related to diabetes. In the earlier stages, capillaries (small blood vessels) in the back of your eye can enlarge and form pouches. This can lead to swelling and bleeding that distorts your vision.

This condition can also advance to the proliferative form, in which damaged blood vessels of the retina close off and force new blood vessels to form. These new vessels are weak and may bleed. The proliferative form of diabetic retinopathy can lead to permanent vision loss.

Read more about the four stages of diabetic retinopathy.

Macular edema

Macular edema results from diabetic retinopathy. When capillary walls lose their ability to control the passage of substances between the blood and the retina, fluid can leak into the macula, causing it to swell. The macula is the part of your eye that lets you see faces and read.

This condition causes blurred vision and potential loss of vision. Prompt treatment is often effective and can help prevent vision loss.

All you need to know about macular edema.

Over time, high blood sugar levels can affect your kidneys’ ability to filter waste out of your body. When this happens, substances such as protein may incorrectly pass into your urine. This progressive damage to your kidneys is called diabetic nephropathy.

You are at higher risk for kidney disease if you also have high blood pressure. Diabetes is the leading cause of kidney disease. If not treated, diabetic kidney disease may lead to the need for dialysis.

Learn more about diabetic nephropathy.

Excess sugar in your bloodstream can damage the nerves of your body. This can happen to the nerves that control automatic processes such as digestion and to the nerves that control your extremities, such as your feet. This can lead to:

  • tingling
  • numbness
  • pain
  • burning sensations

If numbness becomes severe, you may eventually not even be able to notice an injury until a large sore or infection develops.

Learn more about diabetic neuropathy and type 2 diabetes here.

High blood sugar levels can damage the blood vessels in your body. This can cause problems with circulation and increase the risk of cardiovascular complications such as heart attack and stroke.

People with diabetes are more likely to experience foot problems because of nerve and blood vessel damage and restricted blood flow to their extremities.

If you have diabetes, it’s crucial that you take foot problems seriously. Without proper care, small sores or breaks in your skin may turn into deep skin ulcers. If skin ulcers get larger or grow deeper, they can lead to gangrene, which can require foot amputation.

Skin complications, such as bacterial and viral infections, are often the first symptoms of diabetes. Diabetes can also cause specific skin conditions, such as diabetic dermopathy, diabetic blisters, and necrobiosis.

Learn more about type 2 diabetes and skin health.

Long-term complications of diabetes develop gradually. The longer you’ve had diabetes, the higher your risk for complications.

However, proper preventive care can help you lessen or avoid many or all of these diabetes complications. The more effectively you manage your blood sugar levels, the lower your risk of developing complications and the better your long-term outlook.

In the last 20 years, the rates of several major diabetes complications have decreased among adults in the United States.

Diabetes complications often share causes and risk factors. Making changes to improve your overall health can also help reduce your risk of several complications. You can improve your diabetes outlook by:

Diabetes is a lifelong condition, and without proper management, it can cause numerous complications. These include chronic kidney disease, nerve damage, and conditions that affect your eyes, feet, blood vessels, and skin.

Reaching or maintaining a moderate weight, leading an active lifestyle, eating a healthful diet, and following your treatment plan can help you manage diabetes.