Werewolf bites cannot kill an Original vampire, as Elijah Mikaelson mentioned to Elena Gilbert when they were talking about how to kill Klaus Mikaelson. However, it does weaken them temporarily, as Rebekah Mikaelson felt dizzy and had severe hallucinations after drinking a beer laced with a concentrated dose of hybrid venom. It wore off within hours; she just had to rest for a while for her body to metabolize it.
In The Rager, it was shown that somebody can extract werewolf\hybrid venom by using a syringe inserted into the werewolf in question's gums to take a sample. From there, it can be used mixed in food or drink (such as when Connor Jordan injected it into a keg of beer that was delivered to Rebekah's party) or can be used to fill or coat bullets (such as when Galen Vaughn used werewolf venom-laced bullets to shoot Damon in Graduation), and it will affect any vampire who ingests it or is otherwise infected with it. Unlike werewolf bites, hybrid bites are fatal to vampires much more quickly-- typically a vampire will die or be on the verge of death within twenty-four hours, as seen in the case of Nadia Petrova.
The only known cure to the bite of a werewolf is the blood of the original hybrid Klaus, though it is speculated that the blood of Klaus' daughter Hope could also be used. However, Dr. Wes Maxfield thought it possible to synthesize a cure from the venom of a werewolf itself, this theory was never tested. In While You Were Sleeping, the Travelers were able to find a cure for Elena, who was injected with a form of the Ripper compound that was laced with werewolf venom, suggesting that it is possible for science to create an antidote, but this has yet to be discussed further.
It has not been shown how a werewolf bite would affect a human in the case that they are attacked (which is unlikely due to their ferocity and above-vampire prowess). When the supernatural vampire hunter Connor laced the keg of beer at Rebekah's party with werewolf venom, quite a few humans drank it with seemingly no consequences, so it can be presumed that werewolf venom itself has no effect on typical human beings. Klaus fed on Camille O'Connell in Après Moi, Le Déluge and she felt fine.</p>
Vampires bitten by Werewolves/Hybrids
- Damon, Elena and Rebekah are the only main vampires who have suffered the effects of werewolf venom without actually being bitten by a werewolf or hybrid (Though Damon had also been bitten by a werewolf prior to that experience)
- Damon mercy-killed Rose and Will before the effects of the werewolf bite could be fatal.
- Nadia Petrova is the first and only vampire shown on screen to die solely due to a werewolf/hybrid bite so far.
- It was speculated by Wes Maxfield that because werewolf venom is a toxin, it could presumably have an antidote created by scientific means rather than Klaus' blood. However this was never proven only mere speculation.
- In While You Were Sleeping, the werewolf-venom-enhanced Ripper Compound that Elena was injected with was later cured thanks to the antidote created by an ally of the Travelers and delivered by Enzo. This suggests that a scientific cure for werewolf bites may be possible.
- Mikael, like the rest of the Original vampires, cannot be killed by werewolf bites. However, he demonstrated in Live and Let Die that because of his indomitable will and warrior instincts, he is capable of fighting through the effects of the werewolf venom with great focus. As a result of this ability, he was able to recover from the bites much faster than his children Elijah and Rebekah did when they were infected with the venom. In From a Cradle to a Grave, Mikael drank the blood of vampires who had been bitten by numerous werewolves with little to no negative effects, as well.