my german shepherd is 18 weeks old and i have been following her worming progranne
but was wondering just how many drontal i should be giving her and how often
thanks

Be guided by your vet. I worm mine every month till 6 months then every 3 months thereafter. The dosage is according to the weight of the dog.
:)

There seem to be very different practices on worming - presumably it depends on the product. But my dog is on drontal with half a tablet every 6 months. My vet did say that if my dog was frequently around small children that the frequency should be increased to every 3 months.

be guided by your vets recommendation.