Super antipoison potions are made by mixing irit leaf and unicorn horn dust in a vial of water, giving 106.3 Herblore experience. It requires level 48 Herblore to make.
Super antipoison potions cure poison and provide immunity to poison for 6 minutes.
A superantipoison (1) can be found in the southernmost collapsed building north-east of the Observatory, near the entrance to the Observatory Dungeon with a respawn time of 55 seconds.
It should be noted that Antidote++ cures poison, provides immunity to poison for 12 minutes, and is also the cheapest alternative.
Creating a Superantipoison from scratch in the Seers/Catherby Area is a requirement to complete the Medium Kandarin Diary.