FLUTD: a group of problems, not one diagnosis
Similar signs, different care
Possible causes include feline idiopathic cystitis (FIC), stones, infection and obstruction. The name FLUTD does not identify which one is present. A cat who had one cause before can have a different problem later. Do not reuse old treatment without asking the clinic.
What the vet may check
An examination and urine testing are common starting points. Imaging, blood tests or a urine culture may be needed depending on the cat. International Cat Care notes that bacterial infection is not the explanation for every urinary problem; antibiotics are a clinical decision, not a default home remedy.
What to bring
Describe timing, whether urine actually passed, discomfort, appetite and any prior episodes or medicines. A photo of the litter or a brief video may help, but do not delay care to collect evidence. Suspected obstruction needs emergency attention.