Anesthetic Poison

Anesthetic Poison was a poison that rogues could buy in two ranks. Every time the rogue hit with the poisoned weapon, there was a 50% chance of the victim taking damage and being dispelled of one Enrage effect. In addition, its poison damage caused no additional threat, so a rogue could use it in lieu of other poisons to lower their threat. Unlike other damaging poisons, Anesthetic Poison did not scale with attack power.

In Patch 4.0.1 the ability to dispel Enrage effects was built into Shiv and this poison was removed. As of Patch 4.0.3a you can still buy it from scrapbots, though it doesn't work and will disappear from your inventory upon logging out.