[anonymous]

Dogs that get bladder stones often have a genetic predisposition (struvite and calcium oxalate are the most common), not enough water is another contributing factor.
Has she had an x-ray/ultrasound to rule out bladder stones? Because, they can have more than one type of stones. This also. can result in recurrent urinary tract infections.
Add water to the kibble, and you can also presoak the kibble in water overnight in the fridge prior to serving.
Offer frequent bathroom breaks/opportunities to urinate, keep the bladder flushed. Stagnant conditions in the bladder are conductive to stone formation.
Don’t free feed, 2 or 3 small meals a day is better and always have fresh water available. Maybe add a little plain chicken broth (no onion) to the kibble.
A blocked urethra is a medical emergency and can result in surgery to save the dog’s life.
Did the vet talk to you about prescription meds for stubborn cases? Don’t confuse supplements with medication.
Work with your vet, prescription food and all, when the dog has been stable for 6 months to 1 year you can discuss diet changes.
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Ps: You may find some helpful information here http://skeptvet.com/Blog/?s=urinary+tract+infection
Btw: I’d skip the supplements, glucosamine and such. They don’t really help and could contribute to the formation of bladder stones.
Increase water intake and frequent bathroom breaks, opportunities to urinate is your best bet, just add water to the kibble of your choice, they lap it up to get to the food.
This is not veterinary advice; consult your veterinarian.