If your cat has worms and you give him a worming tablet, he/she shouldnt really be "sick" afterwards. The cat may have a bit of diarrhoea for a day (or two at the most), but that's about the only thing I've ever noticed after worming. Some cats may be "off-colour" and feel unwell after the worming tablet, but again, in a day or so should be their normal self. If you're concerned at all, phone your local vet and explain why you think your cat is sick.
Again ~ I've had cats all my life and none of them have ever been sick after being wormed.
All the best....
Again ~ I've had cats all my life and none of them have ever been sick after being wormed.
All the best....
