Patient education: Low blood sugar in people without diabetes (The Basics)

What is low blood sugar? — 

This is a condition that happens when the level of sugar in a person's blood gets too low. Some symptoms of low blood sugar are mild, such as sweating or feeling hungry. Others are severe, such as passing out. Another word for low blood sugar is "hypoglycemia."

Low blood sugar happens most often in people with diabetes. It is uncommon in people who do not have diabetes. People without diabetes might feel like they have low blood sugar sometimes, but their symptoms most likely have another cause.

What causes low blood sugar in people without diabetes? — 

Causes include:

●Certain medicines

●Drinking alcohol, especially drinking a lot over a few days without eating enough

●Certain illnesses that affect the liver or kidneys

●Anorexia nervosa – This is an eating disorder that makes people lose more weight than is healthy.

●Growths or other problems in the pancreas – The pancreas is an organ that sits behind the stomach (figure 1). It makes hormones and juices that control sugar levels in the blood and help the body break down food.

●As a side effect of weight loss surgery

●Hormone conditions – These include conditions that some babies are born with, and others that can develop over time.

What are the symptoms of low blood sugar? — 

Symptoms can include:

●Sweating or shaking

●Feeling hungry

●Feeling worried

If low blood sugar levels are not treated, severe symptoms can occur. These can include:

●Headache, blurry vision, or feeling dizzy

●Feeling weak or having trouble walking

●Acting confused or not thinking clearly

●Passing out

Some people have symptoms within a few hours of eating a meal. Other people have symptoms when they haven't eaten for many hours.

How do I know if I have low blood sugar? — 

To be diagnosed with low blood sugar, you must meet certain conditions. You must:

●Have symptoms of low blood sugar

●Have a low blood sugar level when you have the symptoms

●Feel better after you eat something that raises your blood sugar level to normal

To check if you meet these conditions, your doctor will do blood tests when you have symptoms of low blood sugar. Or they might ask you to check your blood sugar at home. Your doctor might have you do things to cause symptoms so your blood sugar can be measured at the right time. For example, they might have you stop eating for a certain amount of time.

After your doctor confirms that you get low blood sugar, they will look for the cause. To do this, they might order tests, including:

●Other blood tests

●CT scan, MRI scan, or ultrasound – These are imaging tests that create pictures of the inside of the body.

How is low blood sugar treated? — 

Treatment involves both raising your blood sugar and treating the cause of your low blood sugar.

Until the cause is found and treated, your doctor or nurse will teach you how you can raise your blood sugar when it gets low. People usually raise their blood sugar by eating or drinking quick sources of sugar (table 1). Depending on your condition, your doctor might recommend that you carry a quick source of sugar with you at all times in case you need it.

Your doctor will also treat the condition that's causing your low blood sugar, if it can be treated. For example, if a medicine is causing your low blood sugar, your doctor can change or stop your medicine. For low blood sugar after weight loss surgery, sometimes making changes to your diet is enough to fix the problem. If you have a growth in your pancreas, your doctor might recommend surgery to remove the growth.

When should I get medical help? — 

Someone should take you to a hospital or call for an ambulance (in the US and Canada, call 9-1-1) if you still have low blood sugar or severe symptoms after having a quick source of sugar.

If you have low blood sugar, do not try to drive yourself to the hospital. Driving with low blood sugar can be dangerous. Once you are in the hospital or ambulance, you will be given fluids with sugar into your vein. This will raise your blood sugar level immediately.

More on this topic

Patient education: Blood glucose tests (The Basics)
Patient education: Anorexia nervosa (The Basics)
Patient education: Weight loss surgery (The Basics)
Patient education: Diet and health (The Basics)
Patient education: Low blood sugar in people with diabetes (The Basics)