It's important to understand your medications and what to do when you become ill. Speak with your doctor about a plan of action. You may need to stop oral medications while you're sick, but always speak with your doctor first. Generally speaking you will want to continue your insulin injections as directed, being cautious to continue eating or drinking carbohydrates. If you are unable to hold down fluids, definitely call your doctor, as you may need to go into the emergency room. Be careful with over the counter medications, as some may contain sugar. Infection and illness can cause rapid changes to blood sugar so it's a good idea to check your blood sugar often when sick, about every 4 hours.