I had complete historectomy 20 years ago. I was treated fro urinaty tract infection with antibiotics. Now I am experiencing brown thick discharge. Would the discharge be coming from the urinary tract infection?

Brown discharge usually indicates old blood.

When you said that you were treated for a urinary tract infection, does that mean that you're done your course of antibiotics?

I would really go back to your doctor and tell him/her what's going on. Sadly no one can give you an accurate diagnosis over the internet.

Good luck.