Dogs typically develop bacterial cystitis, while cats frequently suffer from feline idiopathic cystitis (FIC) linked to stress and environmental factors. Symptoms include straining to urinate, blood-tinged urine, accidents outside the litter box, and excessive licking of the genital area. Diagnosis involves urinalysis, urine culture, and sometimes imaging to check for stones. Bacterial cases respond to antibiotics, while FIC management focuses on stress reduction, environmental enrichment, increased water intake, and prescription diets. Male cats with urinary blockage need emergency veterinary care immediately.