Has anyone had luck with RX for incontinence?

My 86yr old mother has incontinence (urine). For her to have 3-4 night time accidents a week is pretty normal. It's enough urine that she must pulll all bedding off (including a qulited pad) to wash it. She uses one of those lay-over pads, but most times it leaks onto the sheet/pad/mattress below and it all must be washed. I've ordered a full-sized waterproof pad to hopefully avoid so much work to clean up after an accident, that should arrive today. My question - has anyone had success with medication for this? There is no way I could get my mom to stop drinking in the later part of the day - this is one of the first suggestions you read about when you look up the subject online. She is a HUGE coffee drinker (has cups of coffee all day long & into the evening). I've switched her regular coffee for decafe (unbeknownst to her - I buy two containers of coffee, one regular & one decafe & switch the contents so she doesn't know... as she refuses to drink decafe). I bought her several types of vitamin/electrolight water to drink because she doesn't care for just plain water and rarely drinks any. I was hoping that would help. ANYWAY, knowing that cutting out fluids in the pm is not a viable option, I was wondering about meds. Thanks for any info. LT