I take my long haired Tabby to the vet. She gets matted hair by her flanks.
There's just no way she would tolerate me cutting the matted fur. For about
$35.00 she gets a bath, nail trim, and grooming and they either comb out the
wet matted hair or they remove it with a clippers. In my case Isis sometimes
needs to be sedated. If the vet feels sedation is necessary they do it for
an extra $30.00.

If your cat will tolerate all the handling by a vet's office I would suggest
that route. You get a nice fresh smellling pet back as a bonus!

Mike in Illinois

Long-laired ones?

An excellent, and very quick method is to gently dab some household bleach
on to the affected areas with a swab of cotton wool. For any really awkward
tangles, it's best to burn them off using a lighter.

This is a common problem. I always render excitable cats unconscious before
attempting to cut their hair. Dosing them beforehand with sleeping-pills
crushed into a bread & milk mix is a good method, if you've the time. If
not, a quick whack with a wooden rolling-pin or heavy workboot on the head
gets them out of it for about 15 minutes.

Prevention is very often better than a cure. If long-haired cats are fed
minute traces of ICI-brand rat-poison with every meal, their hair will fall
out very quickly, in clumps, rendering matted-hair problems obsolete.