Umm, SL55--that combination is DEFINITELY dangerous.
Why? Adderall is a CNS stimulant. Alcohol is a CNS depressent. When you take both, one doesn't "negate" the other. The other is there, still in FULL effect--you just don't feel it. What's this mean? Hell YES you can drink a lot more--the adderall will keep you from passing out. This means that when you get alcohol poisoning, instead of getting rid of the toxins (puking) and preventiong yourself from drinking more (passing out) you stay awake and drink more. Yeah, good...Worse case scenarios--WORST hangover EVER; or death by alcohol...
Of course, this doesn't prevent many people from doing both, myself included, but is good before-hand-knowledge nontheless. If I take adderall before drinking, I know not to get to the point where I'm completely plastered, because I'm much drunker than I seem.
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"...you'll get the chance to take the world apart and figure out how it works. Don't let me know what you find out."--BTS