Hi, thanks for your question. There are cases where patients have reported hypersensitivity or allergic reactions to prednisolone, which presents with itchiness, tearing of the eyes, rashes etc. I would advise you discontinue the prednisolone and promptly report to your doctor. He might prescribe something else. Furthermore, I believe you have a condition called irritable bowel syndrome from the dry mouth, constipation, fatigue, and negative colonoscopy results. Treament of this condition is mainly by dietary adjustments which include; 1. Increasing your intake of fibres such as fruits and vegetables 2. Judicious water intake 3. Avoid caffeine 4. Avoid legumes such as beans and peas 5. Avoid foods high in lactose and fructose such as ice cream, corn syrup, cheese, etc. In addition to these dietary modifications, you can also take probiotics which help reconstitute the bacterial flora of the gut. With time you should feel some relief. I hope I have answers your question. Best wishes.