Supersonic causes the target to become confused. Confused Pokémon have a 33% chance of hurting themselves each turn, for 1-4 attacking turns (50% chance in Generations 1-6). The damage received is as if the Pokémon attacks itself with a typeless 40 base power Physical attack.

Pokémon with the ability Own Tempo or those behind a Substitute cannot be confused. Soundproof also prevents this move.

When a Pokémon is holding Normalium Z and uses its Z-Power, Supersonic turns into Z-Supersonic and raises Speed one stage, in addition to its usual effect as above.