I am so sorry poor Filipp has been through so much!
He could have UTI, cystitis, strictures from the catheter or be blocked.
I do not want to alarm you but I am very concerned about your boy.These are very serious and can even be life threatening symptoms Any time a cat cant stay out of his box or goes in or out with little or no production he is either sick or in pain.
You should make a trip to the vet ASAP. - If you think he has a urinary tract infection and is in danger of becoming blocked.
UTI's are serious in males because they are caused by sticky crystals in the bladder.At any time they can block the urethra.Since this is going on a while your boy is in great danger.Cats are very stoic animals so crying indicates he has a burning sensation when he tries to void. That is quite painful to him. It must be addressed with pain medication.
If he becomes unable to urinate that is a MEDICAL EMERGENCY . His bladder could burst and he would have to be catheterized to save his life.
If that is the case, you must take him back to the vet right away
He may have a UTI that can be treated economically.
UTI's must be treated with an effective broad spectrum antibiotic like Clavamox or clidimycin and for a long enough duration so all bacteria is eradicated. If not, they will refluorish, stronger and more resistant and reinfect him. In addition, the bacteria can become tolerant of the same antibiotic so the medication should be varied for best results.
The most common cause is a dry food diet:
He must get right to a vet for fluids and antibiotics and pain meds to get him over this.
Please let me know how he is doing.Reply here or if you prefer we can speak on the phone.
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