The Use of Osmotic Laxatives Versus Macrogol for Bowel Preparation in Patients Undergoing Colonoscopy

Inclusion Criteria:

1. Signed informed consent forms confirming the understanding of the course of study and agreement to participate in it.
2. A written patient consent to fill the prepared questionnaire and to perform diagnostic colonoscopy in case of following situations:

   * Routine oncological screening
   * Polyps or neoplasms in anamnesis
   * Anemia or latent bleeding diagnostics
   * Diarrhea or constipation with unknown reason
   * Inflammatory bowel disease in remission
   * Pathological formation according to US examination (neoplasm evidence in abdomen)
3. Suspicious colon neoplasms according to CT and/or irrigography
4. ASA scale for physical status assessment ≤ 3
5. Patients with adequate electrolyte balance rate (K, Na, Cl, bicarbonate rate screening).

Non-inclusion criteria:

1. The baseline data about comorbidities or laboratory data that can jeopardize the safety of the patient or reduce the likelihood of obtaining satisfactory data necessary to achieve the goal (goals) of the study.
2. The presence of progressive carcinoma or other bowel disease, leading to excessive mucous membrane fragility.
3. The confirmed or suspected gastrointestinal (FA) obstruction, stagnation in the stomach, gastroparesis, or a violation of gastric evacuation.
4. The intestinal perforation.
5. The profuse vomiting.
6. The procedure goal to perform a medical procedure (eg, polypectomy, mucosectomy).
7. The presence of toxic colitis or megacolon.
8. Severe acute phase of inflammatory bowel disease as a contraindication to colonoscopy.
9. The presence of acute GI bleeding.
10. History of gastrointestinal surgery (for example, colostomy, colectomy, gastric bypass surgery, stomach resection).
11. The history of impaired consciousness predisposing to pulmonary aspiration.
12. The colonoscopy aimed remove a foreign body or decompression.
13. History of incomplete colonoscopy
14. The confirmed severe renal failure (glomerular filtration rate (GFR) \<30 ml / min / 1.73 m2).
15. The confirmed severe liver failure (10-15 points on the Child-Pugh scale).
16. Dehydration condition requiring treatment.
17. The ascites.
18. Severe congestive heart failure (class III and IV).
19. The state of hyperuricemia with a clinic of gouty arthritis.
20. Pregnancy or lactation.
21. Patients at risk of pregnancy and not using an acceptable method of contraception during the study. Women of childbearing age must provide a negative pregnancy test at the beginning of the study and must use the oral contraceptive method, double (use a condom with spermicidal gel, birth control suppositories or films; diaphragm with spermicides; or male condom and diaphragm with spermicides), injection contraception or intrauterine devices . Non-fertile women - more than a year after menopause, after surgical sterilization or hysterectomy at least 3 months before the start of the study.
22. The hypersensitivity reaction to active substances or to other auxiliary substances (Eziklen and Moviprep).
23. A patient with a mental state that does not allow him to understand the nature, extent and possible consequences of the study and / or evidence of refusal to cooperate.
24. During the course of the study, the patient is likely to require treatment with drugs that are not permitted by the study protocol.

Exclusion Criteria:

1. The pregnancy
2. The inability to follow the protocol
3. Refuse of study participation.