Thrash causes damage for 3 to 4 turns. While Thrashing, your Pokémon
can't use any other attack, and you cannot run, use items, or switch to a
different Pokémon. When your Pokémon is finished Thrashing, it becomes
confused. If your Pokémon is already confused when it begins to Thrash
(because it is using the move twice consecutively, for example), the
Thrashing will immediately end if your Pokémon hurts itself.
Because it is a Normal type attack, it cannot affect Ghost Pokémon.