Cystic fibrosis CF Glucose tolerance test (1303)

Key points below

Cystic fibrosis (CF)

What is a Glucose tolerance test?

The test is done to find out how the body handles glucose (sugar).  If the body does not handle glucose like it should, it can cause diabetes.  Untreated diabetes can lead to serious health problems.   It can also make symptoms of CF worse.

What is Diabetes?

Diabetes is a disorder that affects the way the body uses food for energy.  Insulin is a hormone made in the pancreas. It helps move glucose out of the blood stream and into the cells.  Without insulin, too much sugar stays in the blood.  

With CF, the normal thin mucus that coats and protects the nose, throat, mouth, and lungs gets thick and sticky.  The thick mucus clogs the pancreas.  It keeps the body from making insulin normally. This leads to CF diabetes.

How is this test done?

Three days before the test, you should eat 3 to 4 servings of carbohydrates (carbs) at each meal. This helps the body prepare for the test. Foods high in carbs include: pizza, bread, cereal, rice, crackers, fruit, juice, milk, yogurt, beans, pasta, potatoes, and corn.  Sweet foods and snack foods like soda, juice drinks, syrup, honey, cake, cookies, donuts, pudding, candy, and chips are also high in carbs and fats.  

Special Information


Call your child’s doctor, nurse, or clinic if you have any questions or concerns or if your child has special health care needs that were not covered by this information.