Having a colonoscopy done tomorrow at noon, since taking pico-salax at noon today, i have a severe headache and vomited. should i cancel appt.

Misdirected question: Your question is best directed to the doctor who prescribed your prep and will be performing your procedure. Call the after-hours doctor with your question, if the office is closed. That being said, many patients have difficulty with their preparation before colonoscopy, but the best yield from the test derives from the quality of the preparation you provide your doctor. Good luck with your exam.

NO: Unless you are still ill tomorrow. Some people (especially those with low blood pressure or migraines) can be VERY sensitive to dehydration. You need to drink as much clear liquid as possible now to help the prep work, and to make up for any fluids you are losing after taking it. Try broth or gator ade, something with some salt to keep it in your system. Drink up until the very last minute.