Colonoscopy Prep FAQ

Here are some of our most Frequently Asked Questions about preparing for a colonoscopy:

Will I need to take a day off work?

Yes. You will need to take the day of your procedure off, because you will be sedated and there is no driving afterwards. You must have a driver, such as a friend or family member, with you to take you home after the procedure. No exceptions.

Will I have to change what I eat before the colonoscopy?

You will be on a low fiber diet for 5 days before your colonoscopy. The day before, you can eat nothing except clear liquids, and you’ll start your prep at 4pm. On the day of the procedure, you’ll finish your prep in the morning and can drink clear liquids up to 4 hours prior to your check-in time.

*Please read your 5 day preparation planner immediately upon receiving it.*

When is the last time I can have clear liquids to drink?

You may have clear liquids up to 4 hours prior to your check-in time. Please avoid all liquids that are RED, BLUE, or PURPLE in actual color.

Can I start my prep earlier/later?

Yes, you can start your prep earlier or later than 4pm, but no earlier than 1 hour before start time (3pm the day before your colonoscopy) and no later than 1 hour after start time (5pm the day before).

If I start to vomit during the prep, what should I do?

If you vomit only a few times, take a break, lengthen time between glasses until this resolves. If vomiting is continual and excessive, call the on-call physician at (425) 259-3122.

I drank almost all of my prep and still haven’t gone to the bathroom. What should I do?

During business hours, 8am-5pm, call the GI Prep Line (425) 259-3122, option 4. If it is after hours, call the GI office for the on-call physician at (425) 259-3122.

What happens if my prep is not adequate?

It is very important that you are clean for your procedure, which should occur if you exactly follow the 5 day prep planner. This will improve the chance of visualizing colon polyps or abnormalities during your exam.

If your prep is not adequate, your procedure may be cancelled and rescheduled, or your procedure time will be delayed in order to allow time to drink more prep solution.

If the procedure is attempted but aborted due to a poor prep, you may be asked to return for a second procedure, using more bowel prep and you will be charged for the second procedure.

My family member did a different prep. Can I do the one that they did instead?

No, your prep regimen has been prescribed specifically for you by the doctor.

The pharmacist gave me a different bowel prep, and/or the instructions on the container are different from the instructions on my prep planner. What should I do?

Call our GI office (425) 259-3122 immediately to receive instructions that coincide with your prescribed bowel prep.

How long does the colonoscopy procedure take?

For your colonoscopy, you will be at the Endoscopy center for about 2 hours from check in to check out.

What if I do not have a driver or they cannot stay for the entire time?

Your procedure will be cancelled if your driver is not in the building at all times. This is a strict policy. You have the option of rescheduling your exam.

In certain circumstances the procedure can be done without sedation, though if unsuccessful, you may be asked to return for a second procedure, with a driver and you will be charged for the second procedure.

Will I be knocked out during the colonoscopy?

You will receive anesthesia/Propofol before your colonoscopy. This guarantees sleep throughout the entire procedure, and has a quicker recovery, usually with no nausea and no memory loss.

What if I am having my period?

This will not affect your procedure in any way (tampon or pad okay).

Should I bring my CPAP machine?

No, you will not need your CPAP machine during the procedure.


Review the prep instructions on our Colonoscopy Prep page.