Many people with diabetes regard the insulin pump as a wondrous invention that makes their lives a lot easier and makes their blood sugar easier to control. But even with a pump, things aren't perfect, and when your blood sugar rockets upward for no apparent reason, it pays to know what steps to take to get back on track.

"The pump is not something that you just plug in and it controls your diabetes," says Dr. Dale Hamilton, MD, of The Methodist Hospital in Houston, Texas. "It might actually be a little more work than injections, but for the motivated patient, the pump can free them up a little bit dietary-wise."

The pump slowly and continuously delivers insulin to the body, and as such, it's designed to mimic what a non-diabetic's pancreas does. Today's pumps are smaller and more sophisticated than ever, and many can be controlled remotely. Still, a diabetic on the insulin pump can still have high blood sugar readings. Here's what could be wrong.

1. The insulin itself may not be working. "It doesn't happen daily, but it does happen," Hamilton says. "If insulin gets too warm, for instance, it becomes inactive."

He compares it to what happens when you heat up milk to make cappuccino. If you burn the milk, it's changed permanently and you can't get it to froth properly for your drink. "It's the same with insulin," Hamilton explains. "When it gets too warm, it loses its ability to lower the sugar." This doesn't mean, however, that the insulin is toxic, he says.

2. The tubes of the pump could develop kinks. "The insulin pump is connected to plastic tubing and if it kinks up, it could stop working," explains Spyros Mezitis, MD, of Lenox Hill Hospital in New York City. Patients with insulin pumps are taught how to prevent this from happening but in the event that it does, the pump will usually start to beep a warning.

3. You could be coming down with an illness, in which case you're becoming insulin- resistant and may need more insulin. "If your blood sugar is high and you are getting symptomatic, contact your doctor," says Hamilton. "If you have a urinary tract infection or pneumonia, for instance, you may need more insulin."

4. Though it's "pretty rare," according to Hamilton, pumps can malfunction. Call the toll-free number provided by the manufacturer (check the website), and you'll likely be walked through a series of tests to see if the pump is the problem, Hamilton says.

5. Be prepared for a possible problem with your pump by always keeping syringes and a bottle of insulin on hand for an emergency. If for some reason the pump isn't working properly, you'll have these as backup.

6. The site where the pump is located on your body may not be ideal, says Caroline Bohl, MS, RD, CDE at the Naomi Berrie Diabetes Center at New York-Presbyterian/Columbia Medical Center in New York City. "If the area is a little swollen, that could prevent the proper absorption of the insulin," she explains. "You may just need to change the site."