I have two cats, one male one female, I used to worm them with the drontal worming stuff from the vets every 12 weeks as recommended, but they seemed to be getting worms quite often so took them to the vets and vets said as they are keen hunters they need to be wormed monthly which I have been doing, however one of them has them again and it is just short of a month since they were last done, so just done them again. But Poppy the female cat has just vommited on the garden approx 2 hours after having her tablet, so im wondering whether to give her another one tomorrow or something, but is it dangerous to do this, but im worried she wont have digested the tablet.
Also does anyone have any suggestions as to better/different working tablets to use, as im sure I shouldnt be having to do them every 3 weeks or so.

I'd give her another tablet in a couple of days.

The important thing to bear in mind with wormers is that they don't give any lasting protection from the worms. We're so used to flea treatments which hang about in or on the body for long enough to keep the animal flea free for a month that it sounds strange that the wormers just treat on the day that they're given.

When you give a cat a wormer it clears their worms on that day, but if your cat is catching prey it's likely to reinfect itself within a few days and so will be building up a significant worm loading within a couple of weeks.

There's not a wormer on the market which can give lasting protection like we expect from flea products unfortunately, so my advice would be either to stop your cats going out to stop them hunting or to buy your Drontal pills online so you can buy them in bulk.

Oh- and one other thing. A standard Drontal only treats 4kg of cat, so if either of your cats are larger than that you'll either have to give them a Drontal XL (treats up to 6kg weight) or give them a tablet and a half or two tablets as appropriate.

Thanks for that. We do use the xl drontal for the tom cat cos hes quite a big chappie. Given her an extra tablet to be on safe side.