CColonoscopy is the most valid test method in terms of sensitivity and specificity in the diagnosis of lower gastrointestinal pathologies. With colonoscopy, precancerous polyps in the large intestine are removed, and the cellular structure of the removed polyps are examined by histopathological methods. The success of this screening method, which has an important place in diagnosis and treatment, is higher than other screening methods. In preparation for the colonoscopy procedure, it is mostly recommended to follow a liquid-based diet, to use laxatives 3 days before the procedure, and to empty the intestines by drinking all of the largevolume mixtures containing Polyethylene Glycol (PEG) the day before the procedure. The most commonly used drugs for bowel cleansing are PEGs, sodium phosphate, and sennosides. PEG is an isotonic oral solution, is not digested and absorbed. The most important disadvantages of PEG solutions, which are used safely in many patient groups in bowel cleansing, are that they are taken in a high volume and that they taste bad. Sodium phosphate-containing solutions are laxative drugs, which can be well tolerated by patients due to their low volumes, but should be used carefully against the risk of kidney failure due to their hyperosmolar nature. Bowels should be prepared well to perform good imaging with colonoscopy and to detect and remove existing polyps. In an ideal bowel preparation, colonic mucosa should be clearly visible in colonoscopy and there should be no solid or liquid residue. Insufficient preparation for colonoscopy may cause repetition of the procedure and loss of labor, time and cost for the patient and healthcare personnel. In this review based on the literature, preparation for colonoscopy and patient requirements are included.

Anahtar Kelimeler: Colonoscopy, Preparation, Patient Requirements