The Dr then changed it to Myrbetriq been on it for a month. I'm still leaking. And its like every 27 days my urine feels like fire like acid and I'm scaulded so bad on my legs and stomach. I can't walk I can't do anything it hurts so bad. What could be going on and what else should I do? I was on oxybutyin before for over active bladder and it worked when I had my son 19 years ago..no problem till about four months ago it just keeps geting worse