
I have always used Panacur and still do.
I did have an awful situation with it when it first was sold to em with the makers bottle and instructions and not dispensed by the vet.
I did the 3 5 and 8 week protocol and had very ill pups following the second worming.
I went back to what I had done previously and since, (considering the bitch had been wormed through pregnancy, so very little worm burden likely in pups), I worm at 3 weeks (3 - 3 weeks 3 days) and at 7 weeks (7-7wks 3 days), and then instruct new owners to worm at 11 weeks half way through their vaccination regime if they are being done at 10 and 12 or 1 week after vaccinations finished if being done at 8 and 10, wither way avoids their bodies having too many things at once.
I have now wormed 6 generations of bitches in pregnancy and their puppies., due to this I expect they will have very little encysted larva in their tissues.