So basically, I'm looking to be able to get my first class medical certificate. I was diagnosed with ADHD when I was a kid and a year and a half ago I finally went cold turkey with my meds and I have functioned very well since then. I just finished my first semester in college off meds and I got 4.0s in every class. I read something that with regards to substance dependence that "Substance dependence, except where there is established clinical evidence, satisfactory to the Federal Air Surgeon, of recovery, including sustained total abstinence from the substance(s) for not less than the preceding 2 years." Does this basically mean that I have to be off medication for at least 2 years to be able to not classify under substance dependence? I also read that as long as you have been off medication for at least 90 days you can go for an evaluation plus I don't have a real record of when the last time I stopped taking medication was but it was in the beginning of May 2016 that I stopped. I want to know whatever I need to know to make sure I have a smooth transition of receiving my first class medical.

Personally I think that ADD is probably the most overdiagnosed ‘affliction’.
My guess is you just outgrew it.
Question though: did you decide on your own to quit the meds or was this on the recommendation of a ( new?) Doctor?
My recommendation is to get advise before walking into an AME’s office.
AOPA medical is probably a good start.

Yes I did outgrow to a good extent a still get a couple spasms here and there, but that's only when I'm home and I have my freedom to just let it out, but out in public I have no problem controlling it and it was a combination of both. I stopped taking the medication and my doctor also was supportive of me not taking the medication. I asked my dad because he's been a pilot for 40 years hence why I'm getting into it and he told me to do research as well and from my own research I heard the AOPA medical is a good start.

Also, another question is since I'm not on medication, would I be able to get away with not marking on my application that I have ADHD? Especially since I haven't been on medication for over a year and a half.

No. They will throw you in federal prison for failing to disclose a significant, disqualifying condition (but you'd have plenty of other pilots to keep you company there). I believe both ADHD itself and the meds are disqualifying. Read the fine print on the medical form, the part about federal felonies.

Bad news: You're going to have to jump through some hoops, and spend some dough to get a 1C, and it's not a sure thing.

Good news: Plenty of other folks have been down this road, so you should be able to get accurate advice. Talk to AOPA, or a private aviation medicine consultant BEFORE you do anything with the FAA or an AME.

I agree that this spectrum is often over-diagnosed/over-prescribed. Good Luck.

Well I know ADHD isn't a disqualifier, but the medication is. I was actually planning to go to AOPA to get the help I need regarding this as well. And my dad told me first that I would apply first for a third class and I could have my doctor run the tests as if it was a first class.

I'm pretty sure unresolved adhd is a no go.