Ritalin comes with weird side effects. My partner changed quite a bit in a short time until she herself couldn't stand it anymore. Mostly because the libido died and left a thumb feeling.

So she switched to better amphetamines (Dextro) and side effects turned away. Leaving only the positive, expected, effects essentially.

I took a lot of amphetamines in my life. But Ritalin is the only one I can't stand myself on. It's like a neuroleptic is packaged in (I know it isn't) but it makes so thumb and cold. IMO