For my older cat, the vet gave us a tube of something that we put on her paw every three to five days. It's sticky, so she licks it off and somehow keeps things moving and stops the hairballs/blockages. The tube is relatively inexpensive, and may be worth asking about.
So my almost two year old indoor kitty apparently has fleas (the poor sweet girl is itching a lot, has white flecks all over her back, and there are black specks not only on her fur, but all over my bed as well (where she lounges pretty much 24/7)). At least some of the black specks do show up...