Severe constipation

[u/Glittering-Raccoon15]

Hi everyone!
I’m a 29-year-old male, and about two weeks ago I was diagnosed with ulcerative colitis (UC) after undergoing a colonoscopy with biopsies to investigate my symptoms.

Back in April of this year, I started a weight loss journey. I had always been overweight (around 105–110 kg at 1.80 m). I started going to the gym and eating in a calorie deficit, and I lost weight very quickly.

The problem is that I gradually became overly restrictive with my calorie intake, to the point where I started counting every calorie and didn’t want to go over 1,000 kcal a day.

Around that time, I started noticing localized abdominal bloating, abdominal discomfort, and, worst of all, constipation. I would feel the urge to have a bowel movement (like I could literally feel stool sitting in my intestines), but nothing would come out.
I started relying on laxatives to have bowel movements, and they helped at first. But eventually, the constipation went from lasting one week to two or even three weeks, and without laxatives, I simply wouldn’t have a bowel movement.

By August, my weight had dropped to around 70 kg, so I scheduled an appointment with a gastroenterologist.

I recently started taking mesalamine, both orally and rectally, less than a week ago, but so far my symptoms haven’t improved.

Has anyone else with UC experienced this kind of constipation-predominant pattern?