Immediate Effect
Instant Effect
noun
It's instantly effective! Sounds like something out of Pokemon. This word means immediate effect or instant effect.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own. Watch out for the shortening.
即効で目の疲れを取る方法をお教えしましょう。
I’ll show you a way to instantly remove eye strain.