split dosing of bowel prep agents for colonoscopy

The split-dose regimen has been shown in multiple studies to be better than the day-before regimen for morning colonoscopies. Split dosing is associated with increased patient’s acceptance, tolerability and compliance. It leads to better bowel preparation. Almost all bowel preparation agent or purgative can be split-dosed. This table shows the different bowel prep agents, main ingredients, the evening before the colonoscopy dose, the morning of the colonoscopy dose, and the total volume.

AgentIngredientsEvening VolumeMorning VolumeTotal Volume
Plenvu (Salix)PEG 3350 ES0.5L solution
16.9oz
0.5L solution
16.9oz
1L
33.8oz
Colyte (Alaven)PEG 3350 ES2L solution
67.6oz
2L solution
67.6oz
4L
135oz
GoLYTELY (Braintree) PEG 3350 ES2L solution
67.6oz
2L solution
67.6oz
4L
135oz
NuLYTELY (Braintree) PEG 3350 ES2L solution
67.6oz
2L solution
67.6oz
4L
135oz
TriLyte (Alaven) PEG 3350 ES2L solution
67.6oz
2L solution
67.6oz
4L
135oz
HalfLytely (Braintree) PEG 3350 ES,
Bisacodyl
One 5mg Bisacodyl with sip of water
2L solution
None67.6oz
MoviPrep (Salix)PEG, Na sulfate, NaCL, KCL, Na ascorbate, ascorbic acid33.8oz (MoviPrep powder + 1L water)
16oz water
49.8oz
33.8oz (MoviPrep powder + 1L water)
16oz water
49.8oz
99.6oz
SUPREP (Braintree)Na sulfate, K sulfate, Mg sulfate16oz (6oz Suprep powder + 10oz water)
32oz water
48oz
16oz (6oz Suprep powder + 10oz water)
32oz water
48oz
96oz
OsmoPrep (Salix) Na phosphate tablets20 tablets
40oz water
40oz water
12 tabs
24oz water
24oz water
64oz water
Visicol (Salix) Na phosphate tablets20 tablets
56 oz water
56 oz
20 tablets
56 oz water
56 oz
112oz water
Prepopik (Ferring)Na Picosulfate, Mg oxide, citric acid5oz Prepopik solution
40oz water
45oz
5oz Prepopik solution
24oz water
29 oz
74oz
CLENPIQ (Ferring)Na Picosulfate, Mg oxide, citric acid5.4oz CLENPIQ solution
5.4oz
5.4oz CLENPIQ solution
5.4 oz
10.8oz
Miralax (Bayer) with GatoradePEG119g PEG 3350 powder
32oz Gatorade
32oz
119g PEG 3350 powder
32oz Gatorade
32oz
64oz

How to do the split dosing

  • Do not consume the entire bowel cleansing agent at once or on the same day.
  • Take half the total dose of the bowel cleansing agent the evening before your colonoscopy. This is usually between 5:00-7:00 PM.
  • Continue to consume clear liquid diet after the first dose of the bowel cleansing agent.
  • Take the second half of your bowel cleansing agent on the day of your colonoscopy, about 4-5 hours before your scheduled colonoscopy.
  • Do not consume anything at least 2 hours before your colonoscopy.

 

Video on how to use bowel cleansing agents

 

 

Suggested Reading

How to use your bowel cleansing agents for colonoscopy. 

Medications and foods to stop before colonoscopy.

How to tell if your bowel is clean prior to colonoscopy.