Thanks for providing more information.
As per your description,firstly your symptoms suggests the possibility of Gastroesophageal reflux disease rather than peptic ulcer.
So Dexilant is doing a great job for you.
Now as you have rectal bleeding which can be associated with Colon polyp,Hemorrhoid,Anal fissure,Inflammatory bowel disease.
CT or Ultrasound don't usually detect such causes.
And further ano-rectal examination,stool analysis,Colonoscopy should be advised.
If you have profuse bleeding then you need to be seen by your family doctor ASAP.
Aspirin should be avoided after consulting your doctor for a while.
You should take OTC Prilosec in the meantime until you get new prescription of Dexilant.
Also eat fibre rich diet,metamucil and drink plenty of water.
Avoid caffeine,alcohol,spicy food.
Hope this helps.
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