If you’ve been reading about feline bladder stones, you may have come across articles that say diet and water play an intrinsic role in preventing them altogether. Breed disposition is also a factor.

Additionally, prevention of cat bladder stones is specific to the type of stone present. Here we will discuss the basic types, their causes and handling.

1. Struvite

   Struvite stones have been observed to be most prevalent in Himalayan, Persian, Oriental, and foreign shorthair cats, Chartreux, and Ragdolls, and cases may be recurrent. This is the most common of all feline bladder stones, comprising nearly 50 percent of all cases worldwide.

   Struvites precipitate from alkaline urine (pH 7.0 and above), either as a result of an alkaline diet, urinary stasis, or UTI-causing bacteria that increase the pH of the urine. When the pH of the urine increases, the risk of bacterial growth also increases. It would be advisable to do a urine culture in such cases and administer antibacterial remedies whenever an infection is discovered.

   Therefore, management is geared towards making the urine more acidic. The diet should be low in protein to decrease ammonia. Minerals that promote struvite build-up such as magnesium and phosphorus must be removed.

   Sodium also helps acidify urine and increase thirst drive, which encourages urination to clear feline bladder stones. Otherwise, surgery can be done.

2. Calcium oxalate

   This is the next most common type, comprising about 30 to 50 percent of all cases. Persian, Himalayan, Ragdolls, Siamese, and Burmese cats appear to be more prone, especially in neutered males 5 years and older. Cats with a vitamin B deficiency are also prone to these stones.

   Unlike struvites, these tend to accumulate when urine is acidic, so affected cats rarely get infections (acidic urine is a hostile environment for bacteria to thrive).

   Calcium in the blood also increases, so providing a diet that contains enough calcium and magnesium is important to prevent these types of stones in the cat’s bladder. The diet should be low in protein, sodium, and calcium. Milk and dairy, spinach, parsley, and table salt should be eliminated as they can increase calcium.

   Avoid acidic supplements like cranberry, vitamin C and D, as well as cortisone, as it increases calcium levels. It is also vital to create more dilute urine by providing plenty of water and non-acidifying canned foods.

   Unfortunately, elimination by dietary correction is not possible. Surgical removal by cystotomy or a bladder incision is the preferred treatment method, although cystoscopy, which is less invasive, is possible if the cat is female and the stone is small enough to pass through the device.

   If the urine is too acidic (below pH 6.5), potassium citrate is given to prevent stone formation and balance the pH.

   Since the recurrence rate is extremely high, quarterly or bi-annual urine tests and cultures are the key to preventing bladder stones in cats.

3. Compound or mixed uroliths

   As the name suggests, the composite urolith is a combination of types – an inner core with a smaller outer shell of another mineral. Most have an inner core of struvite surrounded by calcium phosphate and therefore often present with urinary tract infections. Antibiotics may be prescribed.

   Because there are conflicts in the treatment of the inner and outer nucleus (that is, treating the other can promote the formation of another outer mineral), veterinarians recommend surgical removal. Thereafter, medical or homeopathic preventive measures can proceed safely.

4. Urate stones

   Like calcium oxalate stones, these are often seen in acidic urine and occur as a result of uric acid build-up. Males, especially Mau Siamese and Egyptian cats, are more frequently affected due to the way protein metabolism occurs in the liver, leading to uric acid overgrowth. Cats suffering from congenital liver shunts also appear to be predisposed.

   Stones of this type in the feline bladder tend to be small and are commonly found in the bladder, which can cause a urethral blockage.

   A low purine diet (less meat and veal) is desirable to decrease the acidity of the urine. Surgery may be recommended especially when there is a urethral blockage or a portosystemic bypass. Otherwise, stone dissolving medications and homeopathic remedies are administered. Allopurinol is also prescribed to reduce uric acid.

5. Ammonium urate

   These are typical of cats that have portosystemic shunts due to a faulty conversion of ammonia to urea that causes uric acid to build up in the blood and urine. The combination of ammonia and uric acid creates ammonium urate stones.

   Management of this type is similar to that of urate calculations. The high-protein diet is avoided and allopurinol is given, sometimes with potassium citrate.

From what we see, dietary management plays a very important role in the management and prevention of bladder stones in cats, whatever the type. Once your cat has stones, treatment can be tricky, so it’s always best to act early. Give him a well-balanced diet and plenty of water. You can also try all-natural homeopathic supplements like berberis and belladonna, which are effective against feline bladder stones and can even be prepared at home.