Prospective Randomized Open Label Study of the Treatment of Therapy-associated Diarrhea During Percutaneous Radiation Therapy of the Small Pelvis. - Comparison of Loperamide and Tincture of Opium -

Inclusion Criteria: * Age ≥ 18 years * Patients who will undergo a percutaneous radiation therapy in the area of the small pelvis. This includes patients with following malignancies: rectal carcinoma, prostate carcinoma, endometrial carcinoma, cervix carcinoma. * Diarrhea grade 1 and grade 2 (Classification NCI-CTCAE Version 3.0) * ECOG-Grade 0-2 * Enlightenment and written declaration of consent to the participation. Exclusion Criteria: * Pregnant patients or patients in lactation period. * Severe dysfunction of liver or kidneys * Injury or illness of brain e.g. increased intracranial pressure, cerebral arteriosclerosis * Epilepsy * Hypersensitivity to components of loperamide or tincture of opium * Ileus * Toxic megacolon * Pseudomembranous colitis/ antibiotic-associated colitis * Diarrhea associated with fever and bloody stools * Acute increase of colitis ulcerous or bacterial colitis caused by invasive pathogenes * Severe respiratory dysfunction or severely limited lung function e.g. bronchial asthma, bronchitis * Dysfunctional draining of biliary area, biliary colics. * Concomitant or earlier addiction of alcohol or opiates * Severe heart disease * Pheochromocytoma * Acute hepatic porphyria * Cor pulmonale * Morbus Addison * Severe hypothyroidism * Organisational problems or circumstances which prevent a complete collection of required data * Artificial anus * Participation in a clinical trial within the last 30 days before involvement * Participation in an other clinical trial at the same time