Older Dog wetting

My 12 year old border collie has started wetting herself apparently while sleeping. She has been on Rimadyl for several months. I'm curious of this could be causing control loss while sleeping. Has anyone heard of this happening?  

[Jaybay]

I don't think it's the rimadyl.  My dog of about the same age started doing the same thing a few months ago and it turns out she's in severe renal failure.  Get your collie to the vet and bring a first-morning urine sample with you.  If you can't get the sample to the vet in about an hour, keep it in the refigerator in the meantime.  Your vet will also need to run some blood tests.  Renal failure will eventually be fatal, but if the damage is caught early enough, it can be fairly well-managed with some diet changes and medication.  Please don't wait!  Hopefully it will turn out to be a simple urinary tract infection, but in an older dog, you need to check into other things like kidney failure.  The wetting could also be due to simple loss of muscle tone and control due to age, but since it only appears to happen while sleeping, I'm more concerned.