Daggermark's Exchange

Transmutation [poison]
Level: Alchemist* 2, Artificer * 3, Cleric */Oracle * 3, Druid * 2, Hunter * 2, Sorcerer */Wizard * 3
Components: V, S, M (a dose of poison)
Casting Time: 1 Standard Action
Range: personal
Target: you
Duration: instantaneous
Saving Throw: -
Spell Resistance: -
  You swallow a dose of poison with no effect and regurgitate a dose of a different poison (your choice) into the old container (or another you have on hand). Attempt a Craft (alchemy) check against the new poison's DC. If you succeed, you create a dose of your chosen poison. If you fail, the poison you regurgitate is inert. If you roll a natural 1, you expose yourself to the original poison (although you remain immune to that poison if you have venom immunity or a similar class feature or ability). The new poison's price must be the same as or less than the original poison's price.