Most people who have had a colonoscopy would agree that the preparation is the worst part, since during the procedure, patients are sedated or given "twilight sleep" so that they do not feel any pain or even remember the test. However, preparation is usually done at home, and it can be quite challenging.
Why? The goal of colonoscopy prep is to eliminate all fecal matter from the colon so that the physician conducting the colonoscopy will have a clear view. There are several ways to achieve this, and some [doctors and patients will have their own methods that work best for them. There are, however, three main types of preparation: Golytely (also called Colyte, or Nulytely), phospho-soda, and sodium phosphate tablets (Osmo-Prep and Visicol).
GolytelyThis preparation will require a prescription from the doctor. It consists of a gallon jug with a powder mix inside. The patient will fill the jug with water to make a drink out of the powder. The instructions are usually to drink one 8 oz glass of the mixture every 10 minutes until the entire gallon is finished or eliminations are clear. After the first few glasses, bowel evacuation (in the form of diarrhea) will begin. Before the gallon is finished, many people find that their evacuations are totally clear and all the waste material is gone from the colon.
If eliminations do not become clear after the gallon is finished, an enema may be needed. Some people do experience nausea when drinking so much liquid, so the physician may prescribe an anti-nausea medication in case it is needed. Golytely now comes in several flavors to make it easier to drink.
Phospho-sodaPhospho-soda is a powder that is available over the counter either by itself or as part of a kit that also includes a laxative and an enema or suppository. The physician performing the colonoscopy will give instructions on which type of kit to purchase.
Three ounces of the Phospho-soda liquid is mixed with water, or if the physician allows, other clear liquids such as ginger ale. After drinking the Phospho-soda mixture, most patients are instructed to drink at least 3 glasses of another clear liquids. If part of a kit, the rest of the kit (laxative, enema, or suppository) will then be used according to doctor's instructions.
This preparation usually results in a bowel movement anywhere from 30 minutes to 6 hours after it is taken. Phospho-soda is also available in flavors to make it more palatable.
Most physicians will instruct patients to call their office if the preparation does not progress as expected (for example there is no bowel movement at all or the evacuations never becomes clear).
Sodium phosphate (Osmo-Prep and Visicol)
Sodium phosphate tablets are prescribed by the doctor doing the colonoscopy. There are two different brands, depending on which your doctor prescribes -- Visicol, a 40-tablet regimen, and Osmo-Prep, a 32-tablet regimen.
In Visicol, 7 doses are taken in 15-minute intervals: 3 tablets are taken for 6 doses, and then 2 tablets are taken for 1 dose (20 tablets total). The next morning, 3 to 5 hours before the test, the same dosage is repeated (3 tablets for 6 doses, and then 2 tablets for 1 dose in 15-minute intervals for a total of 20 tablets).
The prep begins to take effect about an hour after the first dosage of tablets is taken. A liquid diet is usually prescribed starting about 12 hours before starting the regimen. Potential side effects include bloating, nausea, vomiting, and abdominal pain.
In Osmo-Prep (the newer form), the tablets are taken on the evening before and the morning of the colonoscopy. The evening before the test, 4 tablets are taken with 8 ounces of a clear liquid every 15 minutes for a total of 5 doses (20 tablets total). The next morning, about 3 to 5 hours before the test, another 3 doses of 4 tablets are taken at 15 minute intervals (12 tablets total).
Tips for the prep:- To reduce any anal discomfort, use adult wet wipes or a water spray to clean off instead of toilet paper.
- Keep plenty of clear liquids on hand to drink. Water gets boring and you need to stay hydrated.
- Follow doctor's instructions. You wouldn't want to have to do the prep all over again because you didn't get it right the first time.
- Be prepared to spend most of the day before your test on the toilet. Bring a book.
- Call the doctor's office for help if you have any trouble or don't understand the prep instructions.
Sources:
UMHS Medical Procedures Unit MPU/MPC staff. "" U-M Health System. June 2007. 04 June 2007.
Jan Nissl, RN, BS. "Colonoscopy" Cigna. September 1, 2006. 04 June 2007.
Lester Stine, MD. "Preparing for Colonoscopy." Three Rivers Endoscopy Center. 2004. 04 June 2007.
Salix Pharmaceuticals. "Visicol Product Information." Salix Pharmaceuticals 2004. 17 Jul 2007.
Salix Pharmaceuticals. "OsmoPrep Product Information." Salix Pharmaceuticals 2006. 17 Jul 2007.
