If you're tight on funds and can't afford a visit right away, I suggest go to fleaassasin.com and get the fast acting pills , that should help the initial infestation, , one of those (non prescription) will kill all the fleas typically in about an hour. Then soon as you can afford to, call them and set up a visit for a long term solution. They're very reasonable on visit costs, best I've found in the area, and at 15, the kitty should at least get a quick checkup once in a while to help head off any problems before they get big.
You may be able to get what you need at a local pet store. Is the cat highly infected?
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