Diseases & Conditions A - Z
powered by Talix

Diabetes Complications

Complications of Diabetes

People with diabetes must monitor and regulate their blood sugar constantly. Yet, no matter how careful you may be, there is still a possibility that a problem might arise. Some complications like hyperglycemia, hypoglycemia, and ketoacidosis require emergency care. If left untreated, these conditions can cause seizures, loss of consciousness, and death.

High Blood Sugar (Hyperglycemia)

This serious complication can lead to nerve and organ damage if it occurs frequently or over long periods of time. Your blood sugar can rise to dangerous levels for many reasons. This can happen with fasting or overeating. Stress, illness, or not taking enough glucose-lowering medication can also cause hyperglycemia. Spikes in blood sugar don’t always mean diabetes, but the condition does need immediate emergency care.

Low Blood Sugar (Hypoglycemia)

With diabetes, blood sugar can suddenly drop for a number of reasons. Skipping a meal and working out too hard are common causes. You are more likely to experience bouts of low blood sugar if you take glucose-lowering medications or are in insulin therapy.


This is a complication of diabetes that occurs when the body cannot use sugar (glucose) as a fuel source because the body has no insulin or not enough insulin. If your cells are starved for energy, your body may begin to break down fat. Byproducts of fat breakdown, potentially toxic acids called ketone bodies, build up in the body. This can lead to dehydration, abdominal pain, and breathing problems.

Eye Problems

Diabetes can damage blood vessels in the eyes and cause blurry vision or even blindness. Possible eye conditions may include the following.


These are more likely to develop in people with diabetes. Cataracts cause the eye’s clear lens to cloud, blocking light from getting in. Mild cataracts can be treated with sunglasses and glare-control lenses. Severe cataracts may be treated with a lens implant.


This is when pressure builds up in the eye and restricts blood flow to the retina and optic nerve. Glaucoma causes gradual loss of eyesight. There are drugs that can help slow down the process.

Diabetic Retinopathy

This is a general term that describes any problems of the retina caused by diabetes. In the non-proliferative form, capillaries in the back of the eye enlarge and form pouches. This can lead to swelling and bleeding. It can also advance to the proliferative form. This is where blood vessels of the retina are so damaged that they close off and force new blood vessels to form. These new vessels are weak and bleed.  

Macular Edema 

This occurs when capillary walls lose their ability to control the passage of substances between the blood and retina. Fluid can leak into the macula of the eye and cause it to swell with fluid. This condition causes blurred vision and potential loss of vision. Fortunately, treatment is often effective and can control vision loss.

Foot and Skin Problems

People with diabetes are more likely to have foot problems because of nerve and blood vessel damage and restricted blood flow to the extremities. If you have diabetes, it’s crucial that you take foot problems seriously. With poor care, small sores or breaks in the skin may turn into deep skin ulcers. If skin ulcers get larger or grow deeper, gangrene and amputation of the foot may be the result.

Heart Problems

According to the National Diabetes Education Program, at least 65 percent of people with diabetes die from some form of heart disease or stroke. Your risk of artery disease and narrowing of the arteries (atherosclerosis) is also greater. Other problems with the heart and blood vessels that are associated with diabetes include:

  • peripheral artery disease (damage to blood vessels that supply the legs and feet)
  • high blood pressure (hypertension)
  • high cholesterol


Excess sugar in the bloodstream can injure the blood vessels and damage the nerves in extremities such as the feet. This can lead to tingling, numbness, pain, and burning sensations. If numbness becomes severe, you may eventually not even be able to notice an injury until a large sore or infection develops.

Other Complications

Some other possible complications of diabetes include:

  • skin infections
  • urinary tract infections
  • kidney disease and kidney failure
  • erectile dysfunction


According to the Centers for Disease Control and Prevention (CDC), diabetes was the seventh leading cause of death in 2010.

Long-Term Complications and Outlook

Most diabetes complications are connected to problems with blood vessels. Long periods of high glucose levels can cause blood vessels to narrow, weaken, and reduce the flow of blood to many parts of the body. The most often affected are the eyes, kidneys, and nerves. Reduced blood flow can cause problems that can be disabling or even life threatening. See your doctor immediately if you are experiencing any such complications.

Long-term complications of diabetes develop gradually. The longer a person has had diabetes, the higher their risk for complications. Proper preventive care can help you control or avoid many or all of these diabetes complications. The better a person is at managing their blood sugar levels, the lower the risk of developing them and the better the long-term outlook.

Content licensed from:

Written by: the Healthline Editorial Team
Published on: Oct 06, 2014
Medically reviewed on: Jan 03, 2017: Peggy Pletcher, MS, RD, LD, CDE

This feature is for informational purposes only and should not be used to replace the care and information received from your health care provider. Please consult a health care professional with any health concerns you may have.
Symptom Search
Enter your symptoms in our Symptom Checker to find out possible causes of your symptoms. Go.
Drug Interaction Checker
Enter any list of prescription drugs and see how they interact with each other and with other substances. Go.
Pill Identifier
Enter its color and shape information, and this tool helps you identify it. Go.
Drugs A-Z
Find information on drug interactions, side effects, and more. Go.



Discounts & Benefits

From companies that meet the high standards of service and quality set by AARP.

Member Benefits AT&T Wireless Cell Phone

Members save 10% on the monthly service charge of qualified AT&T wireless plans.

Member Benefit AARP Regal 2

Members pay $9.50 for Regal ePremiere Tickets purchased online.

Walgreens 1 discount membership aarp

Members earn points on select Walgreens-brand health and wellness products.

Member Benefits

Join or renew today! Members receive exclusive member benefits & affect social change.