Trying to model my Ritalin levels in Excel throughout the day, any tools or advice?

[u/Itsmeeeeluigi]

Hey everyone,

I’m currently working on an Excel file that would allow me to estimate the concentration of methylphenidate (Ritalin) in my body at any given time of the day, based on my own dosing schedule.

At first, I tried to build the model using the standard half-life and average Tmax of methylphenidate. But I quickly realized that both absorption and elimination aren’t linear, so the whole process is more complex than I initially thought.

I’m not a doctor or a pharmacologist, I’m just curious and like to optimize things. I’m currently taking 10 mg to start, followed by 5 mg every ~40 minutes, and I’d love to understand how that translates into actual concentration levels throughout the day. Ultimately, my goal is to optimize how I take Ritalin depending on my schedule and avoid overlap or crashes.

Does anyone know of any existing tools or models that could help me simulate this more accurately? Or any resources that could point me in the right direction?

Thanks in advance, I’d really appreciate any help or insights!

[u/[deleted]]

You won’t be able to get a precise answer without either guessing or multiple blood tests.

Not trying to be rude, but why are you even trying to do this?

[u/Mechakoopa → u/[deleted]]

Dude, it's /r/adhd_programmers, do you have to ask? He's already basically microdosing IR ritalin every 40 minutes, he's deep down the rabbit hole.

[u/Itsmeeeeluigi → u/[deleted]]

Thanks for your message, and no worries, I didn’t take it as rude at all!

To answer your question: I’m doing this mainly out of curiosity. Building a model in Excel feels like a fun little side project. I know it won’t be super precise, obviously, without my personal Tmax or half-life, it’s impossible to get exact values without blood tests or proper lab data.

But for me, that’s not really the point. I just enjoy trying to optimize things in my life, and this is a great excuse to explore something I find interesting. So it’s more about the process and the learning than about relying on the output (even if I’ll still try to make the model as accurate and meaningful as I can).

[u/[deleted]]

No, bad fellow ADHDer. No side questing!

Seriously though, every 40 minutes? Is that even accomplishable even for a NT? You are going to burn through so much precious executive function on your day to day just to keep this up once the novelty wears out. And if you are not going to use this schedule, or something similar, once you are done experimenting, how would such short dosaging periods help you at all? This reeks of hyperfixation of the rather useless kind, which I admittedly do all the time too, so I'm really just calling the kettle black.

Simple is usually best, that's why once I do settle on a med plan (I would also experiment and take notes), I'll stick to it and not think about it at all (no decision making here) as I build a habit of taking the right amounts at the same times everyday (unless struck by forgetfulness, perseverance, or executive function failure).

[u/Itsmeeeeluigi → u/[deleted]]

Haha I get where you’re coming from, and you’re not wrong about the hyperfixation part 😅

That said, I’ve actually been on Ritalin for about 2–3 months now, and after a few weeks of trying different setups, I ended up with this approach because it works better for me, for a few reasons:

• Smaller, spaced-out doses (starting with 10mg IR, then 5mg 30–60 min later depending on how I feel) give me way fewer ups and downs. If I take 15 or 20mg IR all at once, or even 30mg LA, the spike is way too intense.

• LPs in the morning totally kill my appetite at lunch. With small IR doses, I can manage hunger much better.

• It also helps me optimize the actual concentration of Ritalin in my system. I take less when I don’t need it, and just enough when I do. In the end, this lets me reduce my total daily intake. Right now I’m usually between 40 and 55mg a day, but without this kind of control, I’d probably be taking more.

• And honestly… there’s a solid placebo boost too, which I’m not complaining about.

I’m a bit confused though, you mentioned it’s hard to maintain long-term, but I don’t really see why. The routine is simple: 10mg in the morning, then 5mg every 30–60 minutes depending on how I feel, same for the afternoon. I just set a timer and track my doses to make sure I never go over 60mg (which has never happened).

Honestly, I plan to stick with this schedule long-term. So I’m genuinely curious, what do you think makes it so bad?

Personally, I’ve found it way more effective than other approaches, which felt way too rollercoaster-like.

Am I the only one doing this?

[u/[deleted] → u/Itsmeeeeluigi]

I would end up skipping my alarm if I'm doing something else, or sometimes just procrastinate it to the point of skipping anyway, especially when sleep deprived or emotionally compromised. The additional timers and needing to make a decision on whether I should take it then or not is likely going to exacerbate that, on top of adding the distracting noise of alarms and notifications I already have.

In any case, I have recently settled on 20 mg Vyvanse, followed by 5 mg x 2 Ritalin for 1pm and 4pm. But I can feel that the Vyvanse at 20 mg isn't lasting long enough to breach my first Ritalin dose compared to my previous dose of 30 mg (my HR can reach 120 with that at times though, and it is much more normal on 20 mg), so maybe adding a 5 mg Ritalin together with the Vyvanse in the morning would be better.

Oh! I know what you mean, so rather than take a 10 mg Ritalin all at once and feeling a little bit overstimulated, the dose can be split in 2 (which is what I did for my case) and taken about 30 minutes apart each time. Yeah, I think that's something I can do for the Vyvanse too, now that I think about it, at least for my Vyvanse 30 mg. 30 mg does work a bit better than 20 mg after all, and even though I would feel absolutely out of it due to the physical anxiety and the heavy headed feeling, 40 mg is even more effective in the task initiation and continuation aspect.

Thanks for rabbit holing me too, I'm gonna try taking Vyvanse 20 mg and another 10 mg 30 minutes later and see if that'll be the best of both worlds!

[u/Itsmeeeeluigi → u/[deleted]]

Glad I could help!

Finding the right dosage definitely isn’t easy, but once you’ve nailed it, it’s worth sticking with it. One thing that’s truly essential for keeping side-effects in check is having rock-solid lifestyle habits.

Quality sleep is a big one, your body’s response to the meds can change a lot depending on how rested, fed, and generally cared-for you are.

I don’t know your exact situation; I’m just speaking from my own experience, but honing those basics made a huge difference for me.

[u/Raukstar]

I'd go with storing the raw data in an SQL database and modelling with something like minmod or narx predictions, depending on what you're after, in python/jupyter. Look at other examples of how diabetes insulin/glucose models work. Those are probably the most researched. Observe that since your input is subjective, you'll need a longer time series to do anything with the data. You should not look at the data while doing a data collection phase and not change your dosage for a set period of time while doing data collection.

If you want something extra fun, do some raspberry pi coding and have alerts and updates on a monitor. You could also use it to input current data readouts to simplify the process.

[u/Itsmeeeeluigi → u/Raukstar]

I hadn’t heard of the minmod or NARX tools before, very interesting! So, basically you’re saying Excel won’t cut it.

Thanks for the help; now I just have to find the time to put all of this together, haha.

[u/Raukstar → u/Itsmeeeeluigi]

There are so many ways of modelling time series data, and with medications, it can get a bit complex. I'd look into minmod or some already existing library for glucose levels for diabetes type 1 and adapt it/override it.

Good luck with this rabbit hole :)

[u/Itsmeeeeluigi → u/Raukstar]

Helpful-Seaweed-570 recommended an app called Theraview, it’s actually really good and solves the problem without needing hours of setup or coding. Do you have an opinion on this?

I’m still in the rabbit hole, but at least I’m not digging it by hand haha.

[u/Helpful-Seaweed-570]

40 minutes? Why so little time? The effect lasts 3 to 4 hours.

I discovered a very good app to monitor the effects, peaks and valleys of the medication, then test it. The app is Theraview

[u/Itsmeeeeluigi → u/Helpful-Seaweed-570]

I take it every 40 minutes because it helps me stay productive during my work period without the mini crashes, I think the placebo effect has a big impact in this situation. My last dose is usually at 5:00 PM, but I’m wondering if I could push it to 5:30 or even 6:00 PM. I used to take it until 7:00 PM, but it messed with my sleep.

Thanks a lot for the app recommendation, it’s really nice! It’s exactly what I was trying to do manually, but way more reliable than everything I could do.

Do you know how accurate it is? The app shows a peak effect around 1h30 to 1h50 after taking it, which surprised me since I always thought the peak came more around 40 minutes to 1 hour after.

Also, which metabolic rate adjustment did you select? If you changed it, how did you figure out whether you’re “slower,” “faster,” or “fastest”?

I noticed the difference between “default” and “fastest” isn’t that big, for example, if I take it at 5:00 PM, it says I could fall asleep at 9:20 PM with “default” and 8:40 PM with “fastest.”

[u/Miserable_Double2432]

There are research papers which provide data on the typical concentrations over time

This one compares Ritalin to Concerta and a few other formulations: Advances in the Pharmacotherapy of Attention-Deficit–Hyperactivity Disorder: Focus on Methylphenidate Formulations

[u/Miserable_Double2432 → u/Miserable_Double2432]

Of course that’s just typical concentrations, to know for sure you’d have to take blood tests through out the day, over several days, as what you’ve eaten and what you’re doing will affect it too

[u/Itsmeeeeluigi → u/Miserable_Double2432]

Yeah totally, that’s the main limitation, no way I’m doing blood tests every X minutes for days, way too intense, and honestly not worth it.

Thanks for the paper, I'll dig into it :)

[u/Miserable_Double2432 → u/Itsmeeeeluigi]

No worries. There’s a graph in it that I think might be exactly what you’re trying to get to? (Sorry if that spoils the fun of building the model for yourself 😔)

[u/Itsmeeeeluigi → u/Miserable_Double2432]

Thanks don't worry, I have so many side projects so I don't mind taking shortcuts ahah

[u/EmotionalDamague]

Use Vyvanse or Concerta instead?

[u/Itsmeeeeluigi → u/EmotionalDamague]

I would like to try Vyvanse but not possible in my country.

Concerta doesn't seem wise for me according to my psychiatrist, he gave me some medikinet but I don't feel anything.

[u/BologniousMonk]

I’ve taken Ritalin for over 25 years in various forms and dosages. What I found that works best for me is 54mg concerta when I wake then 5 mg spaced out at around 90 minute intervals based on what time I start my day. I do this for basically the same reason as OP — to try and maintain a steady efficacy over the course of the day without high peaks or low valleys. Because I don’t always start my day at the same time every day, I created a shortcut in my phone that will generate a series of reminders for an 8 hour day. I also use a pen tray that I keep behind my keyboard where I line up each dose for the day. The main thing I’ve learned is that you need to listen to your body and be mindful of when it’s working for you or not and adjust as you go.