as rescue goes, all outdoor cats, and kittens brought in are automatically given liquid strongid on day one (mix in tuna or if friendly, straight up), second dose on second day and last dose 2 weeks later- AND it keeps changing!!) It's a matter of killing adults and the eggs, Strongid kills roundworm and other worms but not tape worm or eye worm or lung worm. Eye worm is predominant in CA and lung worm I only know about because I had 3 feral kittens that had a horrible cough, and cough, and cough (no diarreah or loss of appetite, just this dry continuous coughing...), and the vet did a stool sample and there they were, thought to be from eating birds and mice (raw meat). SO, as worms vary across the US, I'll bet they vary across Europe as well!
For tape worm, Droncit- 1 dose.