How Illness Affects Blood Sugar Levels

Kids with diabetes get sick once in a while, just like other kids. However, because the effects of illness on the body can raise or lower blood sugar levels in people with diabetes, a few extra precautions are needed to keep blood sugar levels under control.

With proper planning and some advice from your doctor, you'll be prepared to handle sick days with confidence.

When your child gets sick — whether it's a minor illness like a sore throat or cold or a bigger problem like dehydration or surgery — the body perceives the illness as stress. To relieve the stress, the body fights the illness. This process requires more energy than the body normally uses.

On one hand, this is good because it helps supply the extra fuel the body needs. On the other hand, in a person with diabetes, this can lead to high blood sugar levels. While stress tends to make blood sugar rise in people with diabetes, some illnesses cause loss of appetite, nausea, or vomiting. The poor intake of food in such cases can result in low blood sugar levels in someone taking the usual doses of insulin.

In a nutshell: Blood sugar levels can be very unpredictable on sick days. Because you can't be sure exactly how the illness will affect your child's diabetes control, it's important to check your child's blood sugar levels often on sick days and adjust insulin doses as needed.

Advance Preparation

Your child's diabetes health care team will include sick-day instructions in the diabetes management plan, which might include:

• how to monitor both blood sugar levels and ketones when your child is sick
• which over-the-counter and prescription medicines are OK to give your child
• what adjustments you should make to your child's food and drink and medications
• when to call the doctor or another member of the diabetes health care team

In addition, kids with diabetes should get the pneumococcal conjugate vaccine (PCV), which protects against some serious infections, including certain types of pneumonia, blood infections, and bacterial meningitis. Kids with diabetes should also get a flu shot every year. These vaccines may help cut down on sick days.

When Your Child Is Sick

While your doctor will give you specific advice about what to do when your child is sick, here are some general guidelines:

• Stay on track. Unless the doctor tells you to make changes, be sure your child keeps taking the same diabetes medications. It's important for your child to keep taking insulin during illness, even though food intake may be reduced. The liver produces glucose and releases stored glucose into the blood, so even if your child is not eating very much, the body still needs insulin to process the glucose. In fact, some people need more insulin than usual on sick days — and some with type 2 diabetes who don't take insulin might need some. Without insulin, the body starts to burn fat, ketones build up in the blood, and diabetic ketoacidosis can occur.
• Keep a close eye on blood sugar and ketone levels. Blood sugar levels should be checked frequently — your doctor will advise you on how often. Urine tests for ketones are often positive during illness (even in kids without diabetes) when a child's intake is poor and the body has shifted to using stored fat for energy. But for kids with diabetes, testing can provide an early warning sign that levels in the blood may be building up enough to cause diabetic ketoacidosis. The diabetes treatment plan should guide you as to when and how often to check ketones.
• Pay special attention to nausea and vomiting. Kids with diabetes occasionally catch a bug that causes nausea, vomiting, or abdominal pain. But because these can also be symptoms of diabetic ketoacidosis, it's important to closely monitor blood glucose and ketone levels and seek medical help according to the guidelines in the diabetes treatment plan.
• Prevent dehydration. Have your child drink plenty of fluids. Offer beverages that your child likes that won't worsen symptoms like nausea. Your doctor can advise you about what to give to help manage the illness and maintain control of the diabetes.
• Use medications wisely. Although doctors' opinions vary as to whether they're really helpful, over-the-counter (OTC) medications are often given to kids to control symptoms of illnesses like a cold or the flu. These may contain ingredients that raise or lower blood sugar or that imitate symptoms of high or low blood sugar levels. Check with your doctor before giving an OTC medication to your child. Guidelines for using common medications are often included in the diabetes management plan, including what to check on the labels. If OTC medications are given at the right dose, they generally won't have a significant effect on diabetes control. But prescription drugs such as glucocorticoids (like those given for a severe asthma flare-up) can significantly raise blood sugar. Make sure you know the possible effects on your child's diabetes of any prescribed drugs. Contact your doctor if you think adjustments to the diabetes treatment plan might be needed.
• Take notes. When you talk to your doctor, keep information handy about the illness, your child's symptoms, medications and doses taken, what food and drink was consumed, and whether your child kept it down. Also, note any weight loss or fever and record blood sugar and ketone level test results.
• Help your child rest. Kids need rest when they're sick, so encourage sleeping and resting as much as possible. Kids who usually manage diabetes on their own might need help doing so for a day or two.

When to Call the Doctor

Your child's diabetes management plan will include specific guidelines to help you recognize when medical help is required and recommend what actions to take and whom to call.

Generally, though, call your doctor if your child is sick and:

• has a lack of appetite or inability to eat or drink
• has persistent vomiting or diarrhea
• has low blood sugar because of poor food intake — but remember to try to bring it back up (such as by injecting glucagon, if necessary) before calling the doctor or rushing to the emergency department
• has blood sugar levels that are high for several checks or don't decrease with extra insulin
• has moderate or large amounts of ketones in the urine
• might be having symptoms of diabetic ketoacidosis
• his or her food or fluids will be restricted for things like diagnostic tests, surgery, or a dental procedure

Whenever you have questions or concerns, check in with your doctor. Together, you can make sure that your child feels well again soon.

Reviewed by: Steven Dowshen, MD
Date reviewed: August 2010