urinatinating outside box

Question
Our cat is 13  yrs. old.  He had a UTI several years ago and we were told not to let him have tap water, only bottle water.  He started urinating outside the litter box a couple of months ago, went to the vet and was given an oral antibiotic, which he only partially swallowed.  He got better, but now his infection must be back urinatinating outside his box.

I have a bottle of Silver Biotics.  It is unopened but has an expiration date of 2/2010.  The bottle says: 10 ppm, 8 fl. oz. (236 ml.).  Would it be safe to try this on him?  How much would I give?  How would I administer it?  Do you think this bottle would still be good past this date?       

Thank you very much,  

Mr. Kitty and Becky

Answer
I would not give your cat ANY type of human medicine or even a homeopathic one.More cats die because of this than you can imagine. Many, many human drugs and the like are very toxic to cats.

Your cat didn't get well because he wasn't given his full doses of antibiotics. You need to have the vet or a technician show you how to properly give him drops or a pill. I hope that you also changed his food to a more bladder and age friendly diet. That goes a long way in preventing these things.

Call your vet and get another bottle of antibiotics and ask to be shown how to give them correctly.
Only by doing this is Mr. Kitty going to get better. At his age you do not want to wait or mess around with other things.