Urine on clothing. Any advice?

When the urine soaks through the pants spray them with some OxyClean and rinse them out. Then when you do the load of laundry they will not smell or have stains. Make sure to set the machine on a double rinse too.
I had a client who was mostly bedbound but she liked to be dressed. She would crap and pee through her diaper and pants every single day. I would take off her pants, rinse them in the sink, then spray with OxyClean and leave them until I did a wash. It worked every time.

There is one benefit to masks - I chew up a bunch of mints, put on the mask and clean up. Silly but it works!

Sometimes, you just have to toss the offending smelling pants. Mom has some of her 'faves' but they smelled so awful. And nothing could get the smell out. She does her own laundry, about the last 'personal' chore she can do. She uses the tiniest amount of detergent and then basically bakes her clothes dry. The smell is integral to the fabric.

As a last ditch effort, (she is nose blind to any smells) I suggested she treat herself to some new slacks--IDK if she did.

I also have been buying her muu-muus which look so much nicer and they wash up better. All she has to do is pull this over her head. She wasn't wearing blouses or shirts anymore unless she was going out, so she just wore pants and one of those sleeveless housecoats. Not a good look when you have 'our' upper arms. Muu-muus look nicer and are easier when it comes time to go to the toilet.