What is Shampoo Effect?
1.
A residual drug or alcohol phenomonon in which, during a period after a heavy binge, only a small amount of the recently-abused substance is needed to re-activate your buzz. So named after what happens in the shower when you "rinse and repeat": only a tiny bit of shampoo is needed the second time around to achieve a full sudsy lather.
"Man, I've only had one bloody mary and I feel buzzed!"
"Shampoo effect, dude. You were blasted last night."
2.
When because of recent use, a little goes a long way. Usually referred to when re-gaining an alcohol buzz. (If you shampoo your hair and ever "repeat", you know how just a tiny bit of shampoo will cause instant lather? that's the shampoo effect)
I had so much to drink last night, all it took was one beer this morning to get me buzzed again, gotta love the shampoo effect!
3.
(noun) The effect of having that first drink the next day, after a long night of drinking, and it gives you a good buzz right away. Much like how quickly the shampoo lathers as you apply it the second time.
Whoa, dude, I'm gettin' a heavy shampoo effect from this morning's bloody mary.
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