Wow, you guys should do some reading!
First, taking orange juice if you are having a bad LSD
trip is a placebo effect. taking orang ejuice BEFORE and LSD trip to increase the level of vitamin C in your system is a real effect to trip HARDER.
So keep your body well nourished and hit up the vitamin C before your next acid trip.
Grapefruit Juice does the same thing to DXM
(increases the effects). the dosage is kind of alrge though (several glasses several hours before tripping, by the hour, and I dunno if you ever tried to drink that much grapefruit juice, but it isn't the most pelasant thing in the world to do).
To my knowledge, CrookedEye's post was pretty accurate. Hard to say for sure though.