From Stargate Wiki
- "The poison is only deadly to symbiotes."
- — Ren'al
The poison consists of two liquids which when mixed together create a deadly, fast-acting gas killing any symbiotes it comes into contact with, Goa'uld and Tok'ra, the gas also kills Jaffa. The dying symbiote also kills the host. (SG1: "Summit", "Last Stand", "Endgame")
The gas was first created by the Tok'ra as an endgame against the Goa'uld, a small sample was synthesized and given to Dr. Daniel Jackson who went undercover at a summit of the System Lords, intending to use it to kill all of them and throw the Goa'uld into chaos, however due to the rise of Anubis the plan was never enacted. The gas was later used to kill a battalion of Jaffa who were attacking Revanna in order to allow SG-1 to escape. The Tau'ri began to create their own version and The Trust gained possession of a large amount and after stealing the Stargate used it to attack several Goa'uld worlds. General Landry authorized the use of symbiote poison on a compound Ba'al was in on Earth. When the Ba'al clones were captured and brought to Stargate Command, they escaped and Landry ordered that symbiote poison be put through the ventilation in order to stop them. (SG1: "Summit", "Last Stand", "Endgame", "Ex Deus Machina", "Insiders")