Under the name wolfsbane are included at least two flowers of the aconite family. Most especially the name applies to aconitum lycoctonum. But the name sometimes is also given to aconitum napellus, more commonly called monk's hood. Both species contain poisonous alkaloids called aconites.

There is no mention of a vampire being averse to wolfsbane in Bram Stoker's Dracula.
But in a Spanish film version of Dracula, starring Carlos Villerias as Count Dracula, produced in 1931, wolfsbane takes the place of garlic.

In the folklore archives of the University of California at Berkeley, there is the recorded testimony of an immigrant from eastern Germany. This immigrant said that in his native land wolfsbane and silver knives were placed under mattresses and cribs to keep away both werewolves and vampires. (Paul Barber - Vampire's Burial and Death - page 63).

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