There's so much negativity in this thread towards ADHD meds. I want to chime in with my own experience, when I was in elementary school, there were suspicions that I had AD(H)D, and I got tested, but apparently "I was the quietest and most compliant kid they had ever had". Didn't get a diagnosis.
~15 years later, and I have serious trouble with executive function, I am insanely easily distracted, I have trouble with emotional regulation, I was physically incapable of focusing on something that I did not enjoy for more than 10 minutes, ever. I have no idea how I got through college, heck, I almost didn't. In addition to all this, I was hyper, impulsive, and completely incapable of ever taking a second off, I couldn't relax, at all.
At some point, I saw ADHD somewhere, and I decided to take a more serious second look at it, "what actually is this thing?", and it resonated with me to the core. So after that, I pretty quickly got myself a diagnosis, and not much later I got a ritalin prescription.
I have barely any significant side-effects, I'm calmer, I can focus, I can talk to people without losing my train of thought during the conversation, I can relax better, I can take time to prepare my days and weeks; clean my room, make and follow todo-lists, continue work on a single project for more than a week, I could finally read books without going like "oh huh?!" to every single sound around me 10x a minute, etcetcetcetcetcetc...
My life is pretty terrible still for all kinds of reasons, but no, ritalin doesn't make me feel lethargic -- especially not if I take a slightly lower dose than I'm prescribed -- nobody forced this onto me, I'm not doing this for "compliance" or whatever, I'm not abusing this to be more productive or whatever weird Silicon Valley stereotypes there are about ADHD meds.
Ritalin helps me maintain a relatively stable foundation for my disturbingly disorganized life. It's not magic, and there are real downsides to it, but it really, really helps me very, very effectively.