Hi. Your husband appears to be quite ill. I am very skeptical of the diagnosis of the irritable bowel syndrome. Bleeding per rectum is not a symptom of the irritable bowel syndrome. Your husband's gastroenterologist likely made this diagnosis before the onset of weight loss and rectal bleeding. One could have hemorrhoids along with the irritable bowel syndrome which would account for the rectal bleeding. I am also concerned about the blood in the urine which also is not normal and needs to be explained. The appropriate specialist for blood in the urine is a urologist. Your husband also has what appears to be hypothyroidism. With nausea, weight loss, blood per rectum, blood in the urine, and a hypothyroid state, something more global is going on and I would strongly encourage your husband to discuss this further with his physician. Seeking a second opinion is never a bad idea when dealing with a complex situation such as your husband's state of health. I hope this helps.
All the best,
Frank Farrell, MD
Bleeding ex rectum is never normal and should always be medically investigated. For possible causes google rectal bleeding - the Medicinenet site is particularly informative. If your doctor/GI specialist cannot make a diagnosis it may be necessary to rewquest a colonoscopy.
regards
Morecambe