Hi Annpan,
Please please please don't take just my word for it, and talk to your vet who can advise you on what is suitable for your cats. There are lots of worming tablets out there that don't cover all types of worms, and I've heard that cats can have bad reactions to some. I use Drontal which is about £1.50 a tablet - no problems yet! The norm is every three months, but I think you can do it more often if they are real hunting cats - but please check this out first! Apparently worming them gets rid of the nasties that are in their gut at that moment in time, so stops any worms before they get big and cause health problems.
Worms are horrible (tapeworm can leave lovely little 'segments' around your house!), can cause allsorts of health problems and discomfort and can infect humans!!!

Check out the Drontal website
http://www.drontal.com/cat.html for good info.
To make it easier, if you stroke the cat's neck when you give them the tablet it apparently makes them swallow. You can also get smaller tablets if it's difficult, I can't remember what they're called but vets will know.
I don't know why they put that about mice, what do they expect you to do??
