There are 24 options for bowel preparation prior to colonoscopy. These options are based on available bowel cleansing agents on the market. The agents include Golytely, Nulytely, Trilyte, Colyte, Prepopik, Suprep, MoviPrep, Miralax, HalfLytely and OsmoPrep. They are all in liquid form except Osmoprep. Bisacodyl or Magnesium Citrate can be used in conjunction with some of the bowel cleansing agents for enhanced purgative effect. Bisacodyl is often used because it comes in tablet form distinguishing it from the liquid form of the bowel cleansing agent.

Bowel Cleansing Agents Day-Before Regimen Split-Dose Regimen
Golytely/Nulytely/Trilyte/Colyte Yes Yes
Golytely/Nulytely/Trilyte/Colyte plus Bisacodyl Yes Yes
Prepopik Yes Yes
Prepopik plus Bisacodyl Yes Yes
Suprep Yes Yes
Suprep plus Bisacodyl Yes Yes
Moviprep Yes Yes
Moviprep plus Bisacodyl Yes Yes
Miralax and Gatorade Yes Yes
Miralax and Gatorade plus Bisacodyl Yes Yes
Halflytely Yes No
Osmoprep Yes Yes
2 day bowel prep regimen No Yes


Bowel cleansing agents can be consumed in 2 ways; as day-before or as split-dose.  In the day-before regimen, the bowel cleansing agent is completely consumed the day before colonoscopy. In the split-dose regimen, half of the bowel cleansing agent is consumed the day before colonoscopy and the remaining half is consumed on the day of colonoscopy, about 4-5 hours before the scheduled colonoscopy. The split-dose regimen has been shown in multiple studies to be the most effective way to prepare the bowel for colonoscopy. If bisacodyl is used in conjunction with a bowel cleansing agent, it is used before the bowel cleansing agent; usually about one hour before. The 2 day bowel prep is often used for a patient with prior inadequate bowel preparation and involve the use of bisacodyl and a large volume polyethylene-glycol (PEG) based bowel cleansing agent such as Golytely, Trilyte, Nulytely or Colyte in a split-dose fashion.

The 24 bowel preparation options are:

To see all the bowel preparation instructions, click here.