@Kathylp I haven’t experienced a reduction in Botox efficacy, but I’ve only been getting the injections for four years. How long have you been getting them?
How many units do you receive? You *can* increase the number of units. I started at 100 but by the second time, was up to 200 (because 100 wasn’t effective), where I’ve stayed. Most American doctors start you at 100. Doctors in the UK and Australia often start at 300. You can’t go higher than 400 units in your body at any given moment. If you get Botox for any other reason (like for migraines, or cosmetic purposes), be sure your different doctors know about it so you don’t drift into the realm of toxicity, as Botox is in the top two most deadly toxins on the planet. Very interesting to read about it on Wikipedia.
I suspect that your condition is worsening, rather than the Botox not working any more, because Botox tolerance doesn’t occur.
Ask your urologist if you can increase the number of units you receive.