This is an 8 week old kitten. I would be very concerned.How many raisins?
One single raisin or a whole box of them?
Did the cat just chew them up or did the cat swallow them?
What size is the cat? How many pounds?
How long ago did the cat eat raisin(s)?
Is the cat sick, now? (Vomiting? Lethargy? Diarrhea? Etc.?)
You should call the pet emergency hotline and ask what to do.
These are the questions they are going to ask and you're going to need to answer as accurately as you can.
Yes, raisins are not good for cats and dogs. We know that raisins can make a dog mortally ill but the jury is still out on cats. There just isn't enough information because not many cats will even eat raisins.
If Kitty just chewed the raisins up and spit them out, you probably don't have much to worry about.
If Kitty ate a single raisin, she'll probably be okay.
If Kitty ate a whole bunch of raisins, you've likely got a problem on your hands.
Call the pet emergency hotline and answer their questions.
If it was just ONE raisin and Kitty doesn't appear to be sick, they'll probably just tell you to keep an eye on her and call back if there are any changes.
If Kitty is sick or has eaten more than one raisin, they'll probably have you bring her in.
If you do have to take Kitty in, they'll probably check her vital signs and they might induce vomiting. They could give her some medicine, fluids and supportive care.
If Kitty hasn't eaten more than one or, maybe, two raisins and you call the vet, answer their questions and follow their advice, she'll probably be all right but thing-one is to call the vet.
Fingers crossed for you!