Does anyone know the answer and the reasons to the famous "mad scientist" paradox brain teaser?

You have been poisoned by a mad scientist. There are two vials. VialA has a label that reads, "The label on the other vial is true, and this is the antidote." Vial B's label reads " The label on on the other vial is false, but it contains the antidote." Which vial should you drink?