Acquired Tolerance 
Feat 8
Source Pathfinder Advanced Player's Guide
Prerequisites Poisoner Dedication
Trigger You fail a save against a poison.
A small amount of poison, taken at nonlethal doses, can help the body build up a resistance against a more deadly dosage. Reroll the triggering check and use the second result.
Once you use Acquired Tolerance, you can continue to use it against the same type of poison that day, but you can't use it against a different type of poison until after you make your next daily preparations.
For instance, if you used the reaction on a save against Giant Scorpion Venom, you could use it again against giant scorpion venom even if it came from a different source, but you couldn't use it against Nettleweed Residue, Lich Dust, or another poison.
Traits
Anything that doesn't list another rarity trait (uncommon, rare, or unique) automatically has the common trait. This rarity indicates that an ability, item, or spell is available to all players who meet the prerequisites for it. A creature of this rarity is generally known and can be summoned with the appropriate summon spell.
ArchetypeThis feat belongs to an archetype.
FortuneA fortune effect beneficially alters how you roll your dice. You can never have more than one fortune effect alter a single roll. If multiple fortune effects would apply, you have to pick which to use. If a fortune effect and a misfortune effect would apply to the same roll, the two cancel each other out, and you roll normally.