This is a link to a Parkinsons UK Question & Answer session on Bladder and bowel problems: http://bit.ly/ZOFIqw
In case this link disappears again I googled "bladder spasms in Parkinsons" to find it. Right at the very bottom of the page you will see mention of Tolterodine as a possible intervention which I originally googled when I read your post. This was given to me five months before I was dx with PD for an constant urge and frequency which was making life very difficult and it worked like magic to calm things down. When I started PD meds and the urgency completely disappeared and I realised it had been an early PD sign for me. I know you say your wife cannot go when this the painful spasm comes on but its all to do with untoward spasms of a certain kind of muscle in the bladder. Two medications are suggested. Also one of the many Parkinsons UK publications - see publications link on the HOME page - is one on bladder and bowel care and you can download it.
Hope this helps http://www.parkinsons.org.uk/advice/question_and_answer_qa_sess/qa_bladder_and_bowels.aspx
Hi Eileenpatricia, I've edited the first link above so that it goes to the question you're referring to. Do let me know if there are any problems with this. -Ezinda