Earlier quoted context omitted.
I use Ritalin to treat my ADHD and that was my reaction as well. I have developed a thick skin over the years to the FUD around amphetamines. I can also see how dangerous it could be taking a drug like this without getting the dosage calculated right. Interestingly a pretty prolific mathematician, Paul Erdős used amphetamines [1]. Not sure which one(s) though. I don't think he had a prescription but I think it worked…
I think the issue with amphetamines is because if taken recreationally the quantities and methods of taking are vastly different. So when I was at school I was on something like 20mg of Ritalin (0.02g) twice a day via a pill that was digested by my stomach. Even that lead to issues with diet and sleep and anxiety. Whereas if we're at a rave we'll happily share 1g+ (say between 2 of us which is 12x the amount) of amph…
As far as sleep goes I find that it is about the same with or without it since I tend to self medicate with caffeine but I generally go to sleep at as semi-regular time of the night (I say this as I write this from bed). The biggest blocker for sleep for me is getting excited about stupid programming things right before bed and that tends to happen with or without stimulants.
Without Ritalin I seem to be more anxious but its hard to really evaluate that objectively.