Our Jess has been a bit itchy lately too and she's a little scurfy and her coat a bit dry. The vet told me to use evening primrose oil and give her between 500 and 1000mg each day. I gave her her first capsule today so I'll see how it goes.
I also treated her for fleas even though neither me or the vet could find any. We have two cats as well and treated them. You can never be too safe with cats because they bring them in and Jess suffers from flea allergies.