Need your urgent advice! I have inflammation in rectum

[NehpMan]

I am a boy 27 years old. I can’t empty my bowel, there is inflammation in my rectum and doctor after colonoscopy said it must be proctitis, and gave some medicines “ Ciproxin 500 (ciprofloxacin), Metronidazole tablets USP 500mg, NT-TOX (NITAZOXANIDE)”, by taking the pills I instantly got cured, but by the time the medicines were finished, again I have the same problem.
So whenever I have antibiotics its inflammation goes away, but when I don't consume antibiotics it comes back.
there is no bleeding, pus or pain, nothing but only I have inflammation and it blocks my poop, whatever I pressure nothing goes out, only with diarrhea I can empty my bowel a little.
Really need your advice as soon as possible.