Wolfsbane is the common name attributed to a species of plant known as Aconitum. It is also known as Monkshood, leopard's bane, women's bane, devil's helmet or blue rocket.
Wolfsbane often pops up in supernatural fiction relating to werewolves. The properties of wolfsbane may differ from one reality to the next. In the MTV series Teen Wolf, Wolfsbane is a powerful poison that is dangerous to humans, but deadly to werewolves. Victoria Argent put together some wolfsbane, which she used to incapacitate Scott McCall with the intent on killing him.  Derek Hale nearly died after being shot with a bullet laced with Wolfsbane. Vaporized Wolfsbane can force a werewolf to shift uncontrollably between wolf form and human form.
On the NBC series Grimm, Wolfsbane can be used to mask the scent of humans and supernatural Wesen. The blutbad Eddie Monroe smeared Nick Burkhardt and himself with Wolfsbane while tracking a rogue blutbad responsible for kidnapping a young girl named Robin Howell.