Is it true Aspirin is poisonous to cats?

We posed this question to Professor Peter Rothwell from the University of Oxford...

Peter - I'm not sure about cats actually. I wouldn't feel confident about saying anything about that. Chris - I know that dogs can take Aspirin because I use to give my dog Aspirin and buprofen, and I've actually spoken to a vet who informs me that these drugs do work quite well in them as anti-inflammatories because my dog had a bit of rheumatism. I don't know about cats though, I have to admit.