On the other hand,
Drinking a potion or using an oil is a standard action
In many ways, they behave like spells in potion form, and as such their effects can be dispelled by effects like dispel magic using the alchemist's level as the caster level. Unlike potions, though, extracts can have powerful effects and duplicate spells that a potion normally could not.
So how long does consuming an extract take? I'm inclined to believe that it takes just as long as the spell does to cast (e.g. a full round to Enlarge Person, only a swift for Burst of Speed) but I'd love to know if this is ever clarified in the rules or a FAQ that I've missed.