This phoney-bologna word is used by Hank Hill on the television program, "King of the Hill" to describe any type of psychoactive medication, such as Ritalin, Tofranil (used to stop enuresis), Prozac, Xanax, Cymbalta, trazodone, etc. Not so fake any more though; as I've heard it used in conversations over the last several years.
Bobby's taking goopenthal again to help put an end to him pissing the bed every night.

Hey bub, I'm not gonna let you come in here all hopped up on goopenthal!
by Telephony September 3, 2013
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