I wouldnt bother using those products, they don't work. You can get Frontline (which is more effective) from PAH now, or from your vet, but its much cheaper online from places like Vetuk Frontline: Frontline Spot On For Cats and Dogs From Vet UK: For Healthy Happy Pets .

You can also get more effective sprays for the house such as Acclaim, Staykill (which only need using once a year) or Skoosh, as well as wormers such as Drontal, although if your cat won't take tablets, you could use something like Profender which is a spot on wormer (but needs a prescription from your vet) Profender: Profender Medium Cat Pair Pipettes (POM-V) - £7.79