From my blog:
CATS AND URINARY ISSUES Sep 6, ’07 12:39 PM
for everyone

This is not my area of expertise, but this has been my experience: As a kitten, Poppy developed both a weight problem and a UTI. My vet told me to start feeding her special food which he happily sold me *gulp*. Poppy refused to eat it. Back then I was less aware of how to get cats to eat new foods, so I just said the hell with it and bought Purina One’s urinary health food, mixed with weight management. She ate that from then until she was 2 years old. She never had another UTI. Does this mean that this food is as good as the overpriced prescription food, or did I just get lucky? I don’t know the answer, although I suspect the former statement is probably true.

For various reasons, I soon thereafter began researching cat nutrition. I learned about the benefits of wet food, and found that in many cases, that’s all that’s required to prevent future UTI’s. Even the crappy brands like Friskies would be better than dry food!

I don’t claim to be a vet, vet tech, vet student or anything like that. But I know how to research and examine results. I’ve read a bit on this topic which is how I’ve reached the conclusions I have.

At the very least, were I to have another cat with urinary problems, I’d sooner try them on a GOOD QUALITY canned food before shelling out the dough for a "prescription" dry food (or even their canned varieties). That’s because I believe that good nutrition and species appropriate food is much more likely to keep a cat healthy than inferior ingredients which have been tweaked to change their chemical composition.

What should YOU do? If your vet recommends a prescription diet, I can safely recommend that at the very least you get the canned version of that food. That way your cat will get the extra hydration it needs. And don’t feel bad about giving your cat this food – temporarily. It will do what it’s designed to do, so you can be sure that your cat will do well while you do more research. And I would encourage you to do so. Don’t take my word for it – read up on these things for yourself. Stabilize your cat with the prescription food while you look for something better. If canned food (or raw) alone is not helping enough, there are other supplements you could research. I have not done so, but I know that Wysong makes a supplement for urinary issues. "Biotic pH- is designed for cats or dogs needing assistance generating and maintaining an acidic urine to help prevent struvite crystal formulation."

I can’t endorse this particular product, but know that it’s out there. And if it is, there are sure to be others. Again, I would sooner feed good food, with a supplement such as this, than the crappy prescription foods.

UPDATE: I wanted to quote some info I ran across this morning (3.8.08). This info is taken from discussions in WholeCatHealth. While in and of itself it may not answer any questions, it can at least demonstrate that this group would be an excellent resource for anyone whose cat has a urinary problem.

"S/D and C/D are acidifying diets – meant for short-term use to bring down the urinary pH. There are risks associated with long-term use of these diets….." (see the last paragraph for more info on this).

"Feeding a high-quality, low-carbohydrate, meat-based, high-moisture diet reduces risk of urinary problems, incl crystals. Meat proteins provide the amino acids that naturally keep the urine slightly acidic (desirable for cats is 6.0-6.5 pH)…and the moisture (about 78%
for canned and 68% for the premade raw) helps promote urine volume and pee
frequency, which reduces risk of crystal formation. But some cats, even on a species-appropriate diet, can’t maintain pH…so it’s important to monitor the urine, which you can do at home with pH paper or urine dipsticks. If the pH consistently stays about 7.0, then you can add an acidifier such as L-methionine or ammonium chloride to the meat-based
food…and then still monitor to see how the pH is doing."

"Chronic use of acidifying diets leads to metabolic acidosis, which can lead
to decreased bone formation and detrimental effects on calcium, phosphorus,
potassium, and magnesium balance. Potassium depletion, hypokalemia, and chronic
renal failure can result from feeding acidifying diets which have a marginal
potassium content. The use of acidifying diets is also contraindicated in cats
with chronic renal failure as these animals are often already acidotic. The
use of diets high in NaCl should also be avoided in animals with congestive
cardiac failure. Finally, as indicated above, the use of diets designed to
dissolve struvite may lead to a higher risk of calcium oxalate urolithiasis."

The "precription" foods have methionine added to them to acidify the urine – and you could add that yourself. The problem would be for how long and how much to add. If the urine gets too acidic stones can form in the bladder and they usually have to be removed surgically.

I guess now there is a cat litter that will monitor the pH of a cat’s urine.

So I think I would just use the quality canned food (no dry) and have the cat’s urine checked again in three to four weeks.

I would caution you though about taking him off royal canin, we had a male who had the same problem and we stuck him on that food because it was the lesser evil of the other options. Well I did some research and decided to try some stuff that was suggested by some other people on another site and my guy wound up at the vet within 2 months with the same problem.

I wish there was a better option, and there may be now (this was a couple of years ago) but be careful about changing off the s/o completely.

Now my guy had an abnormally small and thickwalled bladder and this was why he was never able to be on another food. Your guy might not be as severe. If I were you I would try to find a pet nutritionist in the area and see what they can suggest.

I wish you the best of luck

*Addition* The diet that I tried with mine WAS a high protein, grain free, wet diet (I did Innova Evo) I think it really depends on how bad your cat is. If your guy is like mine I would not recommend it, but if he has a minor case then you might be fine. I think you should check with a nutritionist because they can see how bad your guy is specifically. I don’t want him to wind up in pain because his case is too bad.

I have had two cats that blocked. The second one blocked twice.

Doing a lot of research on the matter (google feline crystals) I found that MOST cats do extremely well being fed on a high protein low carb WET FOOD diet. Dry food is too dry, and leaves the cat dehydrated – because cats have a very low thirst drive.

most cats (and I qualify because time to time some cats on the right diet will have issues) get off dry food and never have another urinary issue. My two (out of six) are actually on a home made raw diet – a recipe provided by a vet – and haven’t had another health issue since being on it, over two years now.