The crux is that regular resurrection spells simply restore the body. Which the tadpole has integrated with, so it is revived as well. (Along with the fact that the tadpole doesn't necessarily die when the host does. Throughout the game you're constantly finding living tadpoles in dead bodies)

The exception is True Resurrection, which creates a brand new, intact, body and thus Gale and his True Resurrection scrolls should cure the tadpole infection (Also, Gale's orb situation)

Last edited by Taril; 8 hours ago.