My 54 old husband has had deep, thick blood in his stool for over 3 months (yes, I know, he should have told me ;-) In addition, he has pain and discomfort in his pelvic/groin area above the penis. Lastly, he is also lightheaded when he stands up, is short of breath, and has some nausea. We saw a GI doc, and have a colonoscopy scheduled for this week. Any ideas what might be causing this? (To complicate matters, he has had RSD/CRPS for 10 years, and is on opioids for this, which causes constipation issues). Thank you.