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How do I prepare my bowel for an examination?
Last reviewed: 06.07.2025
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The reliability of the results of the intestinal examination depends, first of all, on the correct preparation of the intestine for this procedure. The methods of intestinal examination include fibrocolonoscopy, rectoscopy, irrigoscopy. The patient should remember that these diagnostic methods require an empty intestine, that is, preliminary cleaning of it from feces.
Preparation for rectoscopy
During this preparation, you need to undergo a preliminary examination. Then change your diet. Lunch - at 13.00-14.00 the day before the procedure. Then, after an hour or two, you need to take a laxative with an oil base. This can be castor oil in a volume of up to 50 ml. Dinner - a low-slag diet is needed: avoid raw vegetables and fruits, as well as cabbage in raw, boiled or stewed form. Instead, you need to drink kefir for dinner, you can eat sour cream, cottage cheese, semolina, chocolate and fruit juices or fresh juices. You can also eat baked goods, but not much. Bread made from coarse flour is excluded.
Then you can do a cleansing enema. In the morning - a light breakfast and again a cleansing enema. This is the day when the procedure will be carried out, so capacious enemas are recommended, up to 1.5 liters of heated water. Enemas should be done every quarter of an hour - half an hour. The purpose of these enemas should be complete cleansing of the intestines from food residues.
Preparation for irrigoscopy and fibrocolonoscopy
It should also be very thorough, since the procedures are serious, during which the large intestine is examined. A diet for two days is recommended for such patients. It is called unplanned, in contrast to the slag-free diet in preparation for a rectoscopy.
The day before the examination, a person has lunch, and then at 15:00 takes castor oil - up to 50 ml, as in preparation for a rectoscopy. You can't have dinner - the maximum you can drink is a glass of kefir. And there is one exception: people with diabetes must have dinner, but it should be light - something dairy. In the evening, you need to take 2-3 cleansing enemas of about 1-1.5 liters each, they should contain warm water.
In the morning of the day when the intestines are cleansed, you can have breakfast - again excluding cabbage and fresh vegetables or fruits - they can cause fermentation. Then the person is given cleansing enemas again until the colon is completely cleansed and diagnostic procedures are performed. After the enemas are done, a tube can be inserted into the rectum, through which air is pumped to remove the remains of fecal matter, which can interfere with diagnostics.
These should be highly accurate diagnostic methods and will allow us to identify diseases such as colon cancer, polyps in the colon, as well as benign tumors that interfere with the passage of feces.
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