Oxybutynin: MedlinePlus Drug Information
medlineplus.gov › Drugs, Herbs and Supplements
Oxybutynin is used to treat overactive bladder (a condition in which the bladder muscles contract uncontrollably and cause frequent urination, urgent need to urinate, and inability to control urination) control urgent, frequent, or uncontrolled urination in people who have overactive bladder (a condition in which the ...
The only things I would say are yes push for a pump because you can then adjust for Dawn rises on an hourly basis (cortisol driving your liver to release glucose) . Once my sugar has risen I find it hard to nudge down again without over correcting.
2. I hope your drugs are helping your problem but I'd be concerned about your kidneys if you are with holding fluids. If you restrict fluids your bladder simply adjusts and has a new lower threshold for needing to empty so I don't think that will benefit. Cutting potential irritants like caffeine seems sensible though.
3 Keep pushing for a solution (could be the pump to get more even sugars across the day or more time 'in range') and don't be fobbed off by vague talk of nerve dammage which is a lazy doctors's way of saying 'I do not know' IMO!! It is okay for doctors not to know but they should admit it and be curious to prove or disprove a diagnosis.