Skip to content
My WebMD Sign In, Sign Up

Diabetes Health Center

Font Size

The NIDDK on Hypoglycemia

Rare Causes of Hypoglycemia

Fasting hypoglycemia occurs when the stomach is empty. It usually develops in the early morning when a person awakens. As with other forms of hypoglycemia, the symptoms include headache, lack of energy, and an inability to concentrate. Fasting hypoglycemia may be caused by a variety of conditions such as hereditary enzyme or hormone deficiencies, liver disease, and insulin-producing tumors.

In hereditary fructose intolerance, a disorder usually seen in children, the body is unable to metabolize the natural sugar fructose. Attacks of hypoglycemia, marked by seizures, vomiting, and unconsciousness, are treated by giving glucose and eliminating fructose from the diet.

Galactosemia, a rare genetic disorder, hampers the body's ability to process the sugar galactose. An infant with this disorder may appear normal at birth, but after a few days or weeks of drinking milk (which contains galactose), the child may begin to vomit, lose weight, and develop cataracts. The liver may fail to release stored glycogen into the blood, triggering hypoglycemia. Removing milk from the diet is the usual treatment.

A deficiency of growth hormone causes increased sensitivity to insulin. This sensitivity occurs because growth hormone opposes the action of insulin on muscle and fat cells. For this reason, children with growth hormone deficiency sometimes suffer from hypoglycemia, which goes away after treatment.

People with insulin-producing tumors, which arise in the islet cells of the pancreas, suffer from severe episodes of hypoglycemia.

To diagnose these tumors, called insulinomas, a doctor will put the patient on a 24- to 72-hour fast while measuring blood levels of glucose, insulin, and proinsulin. High levels of insulin and proinsulin in the presence of low levels of glucose strongly suggest an insulin-producing tumor. These tumors are usually benign and can be surgically removed.

In rare cases, some cancers such as breast cancer and adrenal cancer may cause hypoglycemia through secretion of a hormone called insulin-like growth factor II. The treatment is removal of the tumor, if possible.

Research

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) was established by Congress in 1950 as one of the National Institutes of Health, the research arm of the Public Health Service under the U.S. Department of Health and Human Services.

The NIDDK conducts and supports research in diabetes, glucose metabolism, insulin action, and the hormonal controls of blood sugar. Current studies also focus on fasting hypoglycemia, obesity, and insulin resistance.

Resources on Hypoglycemia

American Diabetes Association (ADA)
National Service Center
1701 North Beauregard Street
Alexandria, VA 22311
800-232-3472 or 703-549-1500

The ADA is a private, voluntary organization that fosters public awareness of diabetes and supports and promotes diabetes research and education. The ADA distributes printed information on many aspects of diabetes, and local affiliates sponsor community programs. Local affiliates, located in every state, are listed in telephone directories or can be located by contacting the national office.

WebMD Public Information from the U.S. National Institutes of Health

Is This Normal? Get the Facts Fast!

Check Your Blood Sugar Level Now
What type of diabetes do you have?
Your gender:

Get the latest Diabetes newsletter delivered to your inbox!


or
Answer:
Low
0-69
Normal
70-130
High
131+

Your level is currently

If the level is below 70 or you are experiencing symptoms such as shaking, sweating or difficulty thinking, you will need to raise the number immediately. A quick solution is to eat a few pieces of hard candy or 1 tablespoon of sugar or honey. Recheck your numbers again in 15 minutes to see if the number has gone up. If not, repeat the steps above or call your doctor.

People who experience hypoglycemia several times in a week should call their health care provider. It's important to monitor your levels each day so you can make sure your numbers are within the range. If you are pregnant always consult with your health care provider.

Congratulations on taking steps to manage your health.

However, it's important to continue to track your numbers so that you can make lifestyle changes if needed. If you are pregnant always consult with your physician.

Your level is high if this reading was taken before eating. Aim for 70-130 before meals and less than 180 two hours after meals.

Even if your number is high, it's not too late for you to take control of your health and lower your blood sugar.

One of the first steps is to monitor your levels each day. If you are pregnant always consult with your physician.

Did You Know Your Lifestyle Choices
Affect Your Blood Sugar?

Use the Blood Glucose Tracker to monitor
how well you manage your blood sugar over time.

Get Started

This tool is not intended for women who are pregnant.

Start Over

Step:  of 

Today on WebMD

Diabetic tools
Symptoms, diagnosis, treatment, and more.
woman flexing muscles
10 strength training exercises.
 
Blood sugar test
12 practical tips.
Tom Hanks
Stars living with type 1 or type 2.
 

Woman serving fast food from window
Video
Can Vinegar Treat Diabetes
Video
 
Middle aged person
Tool
are battery operated toothbrushes really better
Video
 

Prediabetes How to Prevent Type 2 Diabetes
Article
type 2 diabetes
Slideshow
 
food fitness planner
Tool
Are You at Risk for Dupuytrens Contracture
Article