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Urethral Obstruction in Cats


Following discharge from the veterinary hospital, the cat should be placed on a special diet; which diet depends on the type of crystals found in the urine. For cats with magnesium phosphate crystals, diets such as Hill’s Prescription Diet Feline s/d, Eukanuba Low pH/S, Purina UR St/Ox, Royal Canin Control Formula, Royal Canin Dissolution Formula, and Royal Canin Urinary SO 30 help dissolve any residual struvite crystals or stones in the urinary bladder. These foods are low in magnesium and aid in maintaining a normal acid urine. In cats fed these special diets exclusively, signs associated with FLUTD will normally cease within the first five to seven days. To completely dissolve all residual struvite crystals or stones, the diet should be followed for one to two months. These diets, however, are high in salt and ordinarily are not used as a maintenance food. It is important to feed only the prescribed diet. Do not feed fish, shellfish, cheese, vitamin-mineral supplements, or table scraps. These foods contain extra magnesium and also produce an alkaline urine.

During and immediately after the dissolution process, you may be asked to monitor your cat’s urine pH at home or to bring in a urine specimen to be checked for struvite crystals under the microscope.

For those plugs or stones that consist of nonstruvite compounds, such as calcium oxalate, there are also diets that will be of some assistance to prevent recurrence. These include Eukanuba Moderate pH O, Purina UR St/Ox, and Royal Canin SO 30.

No matter what type of urolith is present, surgery may be the best option for your cat, especially if the obstruction cannot be resolved. Your veterinarian will discuss the options with you.

WebMD Veterinary Reference from "Cat Owner's Home Veterinary Handbook"

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