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Feline Lower Urinary Tract Disease

What is FLUTD?

Feline Lower Urinary Tract Disease, ​formerly known as Feline Urological Syndrome (FUS), is one of the most common medical problems of cats. It occurs due to the formation of crystals, made up primarily of magnesium, within the bladder. These sand like crystals irritate the bladder lining, causing pain, and allowing bacterial infection to set in.

FLUTD affects both males and females, but due to their anatomy it is a much more serious problem in male cats. Crystals and mucous clumping together can form a plug within the penis which blocks urination. A cat that is plugged and cannot urinate will become ill very rapidly. If not treated in time, the bladder will rupture and the kidneys will fail. Death usually occurs within 24 hours.

Female cats have a wider urethra, so they don’t plug up as easily. They will, however, develop painful bladder infections (cystitis). Cats of either sex can also develop stones in the bladder or the kidneys.

Signs of FLUTD in both males and females are bloody urine, straining to urinate (often confused with constipation), pain on urination, or frequent urination, often outside the litter box. Male cats that are plugged and cannot urinate will often become suddenly and extremely ill. You may see vomiting, depression, squatting in a strange position, reluctance to move or walk, weakness or loud cries of distress. About 1-5% of cats are affected by FLUTD.

​​CAN FLUTD BE TREATED? ​Yes, it can. Females are usually healthy enough to be treated at home. Males that are plugged are anesthetized and a catheter is passed into the bladder, dislodging the plug. The catheter is left in place for 1-3 days to allow the bladder and urethra to heal. Treatment is also given as needed for dehydration, infection and shock.

Both males and females will need to be treated with special diets, antibiotics, and sometimes urinary acidifiers as well. The prescription diets are continued for the lifetime of the cat because without long term dietary management, FLUTD usually recurs.

CAN IT BE PREVENTED? ​​The best way to prevent FLUTD is to feed your cat a diet that is formulated to maintain a low urinary pH and is low in magnesium. Many commercial cat diets have 10 to 20 times the amount of magnesium needed. Read pet food labels carefully, and beware of pet food labeled “low ash.” “Ash” refers to all the minerals, not just magnesium. A food can indeed be “low ash” but still be to high in magnesium. Good foods available to help prevent FLUTD include Science Diet and Eukanuba. Once your cat has had a bout with FLUTD, a prescription diet made specially for this disease should be fed to prevent recurrence.

Encourage frequent urination by keeping your cat’s litter pan clean. Provide plenty of fresh water. Avoid overfeeding to prevent obesity. FLUTD is more common in overweight cats.

Above all, remember that FLUTD in male cats is a true medical emergency. If you think your cat may be suffering from this problem call your veterinarian immediately!