Cat parents report that both silver vine and catnip can cause cats to become hyperactive and very playful, which has the potential to come off as aggression to other cats not wanting to play. ... While most cats respond positively to silver vine and catnip, always monitor your pet when playing with either plant.

Does Silvervine make cats aggressive?

No. Cats do not become aggressive in response to silver vine. In fact, observations by scientists seem to suggest that cats who normally do not get along very well interact more positively with each other after they have been exposed to silver vine and similar plants.

How does silver vine affect cats?

It's also widely used in Japan and China as a cat stimulant. When exposed to powdered silvervine, cats enter a euphoric state that involves behaviours like rolling, chin and cheek rubbing, meowing, drooling and licking. Reactions vary from cat to cat, but the bottom line is that they all go nuts for the stuff.