Cat with Crystals

My elderly neighbor commented to me that she thought her cat marmalade had been peeing outside the box, but she wasn't sure and she couldn't find any pee (this was 2 days ago), today when I went round I noticed the cat squatting and trying to pee on the kitchen floor with nothing coming out, so I said she should take him to the vet, as that coupled with the possible peeing out side the box could be a UTI, She had to take the dog for his Rabies shot so I said phone and see it they will look at marmalade too, they of course fit him in with no problem, I just saw her getting out of her car after the trip to the vets so I went and helped her with some food she bought for Turk(the dog) and she said they couldnt make Marmalade pee so he has a blockage probably crystals, so he has to stay in over night with a catheter, $350

Any way I thought I would ask about the food he should be eating, not usre what he gets, apart from I know its dry, I also know its bad to have high PH in the food, I searched my typing in PH and UTI on the search tool bar but didn't get anything with those words, so I was hoping someone could help me help her make the right decision with food. rather than the vet reomending that she uses the only one they sell...

I used to frequent this site ALL THE TIME but I have been busy and hate to come back just to ask a question...

Marmalade He is such an affectionate cat, head buts and rubs all the time:

She'll probably need to put him on an Rx diet to dissolve the crystals. Wet food is best. sharky should be along for help with UTI friendly foods available in stores.....everything's changed formulas so I don't know anymore!

Marmalade is so cute! I hope he is feeling better, poor baby.