I have reconstituted Adamax, Semax and Selank into Nasal sprays. I highly recommend it for any rats that need cognitive boosts during learning trials.
Instead of using amphetamines to enhance learning, I have found that Adamax is a great replacement for traditional stimulants -- and it has none of the associated downsides.
I believe Humans with such conditions as ADHD may benefit greatly from these nootropics, but I have only done so on my Rat...
Differences:
Adamax is more potent than Semax, and the effects are more pronounced cognitively, but no difference really. It last longer in the body so I would get Adamax for that reason. Selank is quite similar but completely different, brilliant calming effect, should be used for calming or stressful learning situations (such as Rat exams, or Rat Tests) where as Adamax is perfect for studying.
If you had the choice between Semax and Adamax, I say get Adamax.
And if you get one of the two, I say also get Selank too!