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Complications of Diabetes


The Manual's Editorial Staff

Last full review/revision May 2021| Content last modified May 2021
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You get diabetes if your body's normal way of controlling blood sugar isn't working right.

What are complications of diabetes?

Complications are health problems that happen as a result of having a disease. Diabetes damages the blood vessels that supply oxygen and nourishment to your organs. So people with diabetes may have many serious long-term complications.

What causes diabetes complications?

People with diabetes have complications because not enough blood flows to certain parts of their body. Diabetes causes blood vessels to get more narrow over time. Blood can’t flow easily through narrowed blood vessels or reach certain areas.

Blood vessels narrow because:

What types of complications happen with diabetes?

How do doctors prevent complications from diabetes?

Doctors will:

  • Help you keep your blood sugar under control

  • Check you frequently for the first sign of complications

  • Have you do things to prevent complications

How do I keep my blood sugar under control?

How do doctors check for complications of diabetes?

How can I prevent complications of diabetes?


Strictly controlling your blood sugar lowers the chance of diabetes complications. But your blood sugar level may drop too low. Low blood sugar is called hypoglycemia Hypoglycemia "Hypo" means low. "Glycemia" has to do with the amount of sugar (glucose) in your blood (blood sugar). So, hypoglycemia is when your blood sugar drops too low. Blood sugar is your body's main... read more . Blood sugar is your body's main source of fuel, so low blood sugar can cause serious problems:

  • Hunger, sweating, shakiness, weakness, and trouble thinking clearly

  • Passing out if your blood sugar goes too low

  • Sometimes, brain damage if the hypoglycemia isn't treated quickly

Hypoglycemia is a medical emergency and needs treatment right away. To treat hypoglycemia:

  • Eat or drink something with sugar (like juice or candy) right away to raise your blood sugar level

  • If you often have low blood sugar, doctors may need to make changes in your medicines

  • In more serious cases, doctors may need to inject either glucose into your vein or a medicine called glucagon into your muscle

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