The Lycanthrope entry says that they can be cured with Wolfsbane. The Wolfsbane entry makes no mention of this, but the Belladonna entry says it is a cure for lycanthropy.
I assume this is a misprint?
Wolfsbane and Belladonna are the same plant. Probably just an oversight in the editing.
Wolfsbane and Belladonna are two different plants, Aconitum sp. and Atropa belladona respectively. Apparently both can cure Lycanthropy.
AP#45 Broken Moon includes a more thorough explanation of how Wolfsbane works:
Many claim that this dangerous toxin can
cure both the disease and curse of lycanthropy aff licting
a creature. Such a treatment is risky, and is by no means
an assured cure, as the victim must consume the poison
and thus be exposed to its effects. Should she survive
the poison, she is allowed a second saving throw to resist lycanthropy at the same DC as when she first contracted
the aff liction. If she succeeds, the taint is expunged from
her body. If she fails, the wolfsbane has no affect; though
this cure might be attempted again, the health-sapping
nature of wolfsbane has led many to die of self-aff licted
poisoning in the search for their affliction’s cure.
The AP also suggests that the kiss of a dryad or unicorn's blood might work. It says that a remove curse spell can work past the 3-day limit given in the Bestiary, but only if cast while the afflicted is in wolf form.
Belladonna mentions it only works within an hour of infection, whereas wolfsbane can work either within 3 days or perpetually, the text is unclear.
according to Wiki, they are actually two different plants:
Belladona/Deadly Nightshade (Atropa belladona): http://en.wikipedia.org/wiki/Atropa_belladonna
Wolfsbane (Aconitum, related to buttercups): http://en.wikipedia.org/wiki/Aconitum