I am currently looking after a friends boxer while she is on holiday and unfortunately she had a fit on Tuesday. I took her to the vets who diognosed epilepsy and put her on some tablets for it. These have made her incontinent and she wees in her sleep. Unfortunately my living room carpet is absolutely stinking now. I have tried many cleaners to no avail and cant even sit in my living room at the moment. I am taking her back to the vets shortly, so hopefully they will alter her medication to prevent any further occurences. Any ideas about this whiffy problem would be gratefully recieved, thanks.

Sprinkle bicarbonate of soda on the floor, let it sit there for 30mins or longer of poss before hovering it up - that's meant to be great but I don't have carpet so have not tested the theory ;D  It is supposed to neutralise the smell!

Household ammonia is brilliant for getting rid of smells, mix 1 tablespoon to 1 pint of warm water and wipe over the carpet without overwetting.  The ammonia smells strong but as the smell disipates it will take away the bad smell too!
Apparently it's important that you do a colour patch test on your carpet first!

being amonia will this not encourage dogs to pee even more?  i would try the bio washing powder and wash thoroughly then once damp cover with the bicarb, this should sort it out.

I know it would mean expense, but if all else fails, don't some professional carpet cleaners have a speacial cleaning fluid for that purpose - deep steam cleaning with an appropriate product should bring it right out.
Many years ago, we had a dog who was very sick after worming tablets, and the smell it left behind was horrible - we had to get the carpet professionaly cleaned in the end, but it worked.

Yes ammonia would definitely encourage dogs and cats to pee more.

I find "Simple Solution" from pet shops such as Pets At Home to have been the only effective odour remover. I no longer use carpets though. :)