Bladder Augment and Oxybutynin

I had a bladder augment over 20 years ago, back in 1991 at the age of 8. After that time the doctors kept me on Oxybutynin /Ditropan to control bladder muscle spasms. Over the years I stopped seeing a urologist since i moved and a couple years ago my family doctors suggested I didn't need oxybutynin any more since 1. I was on dialysis and 2. the dose was making me extra tired as well as light sensitivity. She mentioned that since I had a badder augment I shouldn't need it. Now that I found a living donor and if all goes well a transplant is going to happen in 3-6 months, and I don't want to damage the new kidney. I will be asking my doctor to send me to Urology but i just want people's experiences here. I have been taking the drug since I was 4 or 5 when they discovered my neurogenic bladder. Had a bladder augement at 8 and they kept me on the drug afterwards. I haven't taken the drug for a couple of years nows. I also self catheterize, since i haven't been able to void on my own since the bladder augment.