Hi. Thanks for your query. Noted your history of pain in abdomen for 20 days, constipation and no relief in spite of Colospa retard and pan-d. Passing lots of gases, lost 10 kg weight. You have not mentioned your age and gender. If elderly the biggest chances are colonic pathology. I would advise in such a case the following: X-ray of the abdomen in standing position, if lots of fecolith, go for saline-soap water enema first to relieve the problem. Ultrasonography of the whole abdomen followed by CT scan if required. Tests of stool, urine and blood to help further diagnostics. Colonoscopy and biopsy if warranted Consult a General Surgeon for clinical evaluation and correlation with tests. This will give better diagnosis and a plan for surgery or medical line of treatment. Make a list of the the foods and beverages that increase your problem. And stop them strictly. Since you have lost too much of your weigh, it is preferable to rule out cancer, diabetes, thyroid problems.