I am glad to help.
FUS (Feline Urologic Syndrome) which is now termed FLUTD (Feline Lower Urinary Tract Disease) is very common in male cats and once blocked and not able to urinate this is a true life and death emergency.
Cats generally can live from 24-72 hours once blocked until they either are provided with relief or this can be fatal. You were correct to rush him to your vet.
FLUTD is also a recurrent condition.
It is critical that your cat eats ASAP or else Feline Fatty Liver Disease may occur which further complicates this issue. I would see your vet and correct this. Valium given by mouth or IV injection, works well to stimulate appetite immediately in cats like yours.
Once your cat is able to urinate freely and is eating, we have had excellent results preventing recurrences in FLUTD cats like yours using 2 natural products both available at www.drcarol.com. VitaLife Cat Supplements and Cat Urine-Eaze.
I hope this is somewhat helpful.
Feel free to contact our office if I can help further.
Best Wishes
Dr Carol Osborne, DVM
My Kitty had urinary troubles that he too had to be catheterized, and was put on med's for a week to help his kidneys/bladder to repair. Since then, we have him on Veterinary Urinary OS food. It's my understanding that it's the cheap food, we buy in the grocery store with so much questionable meal, and ash that is causing this issue with our babies. I have 3 cats, various ages and breeds, and I add 1 can of water packed chunk tuna (chunk is better quality than flaked)with a full can worth of water to their diet everyday. My vet, whom I trust, said if I continued with the cheap food I could see repetitions of this urinary problem. It costs more, so I do without something to pay for it, because I love my flurry friends, who are my babies. Also, make sure your pet is drinking, we had a short glass on the bathroom counter that they drank from, which we rinsed, changed water, everytime we washed our hands, and I changed that with the advised large bowl, because if their whiskers touch the sides, they will not drink as much. I tested this, and my furry friends, drink double the amount. And one more thing. Make sure you give him some wet food everyday, so he'll have water no matter what.
Blessings