I do math for a living. I'm an actuary.

So when I got switched over to extended release from instant release, I got interested in the timing of the doses.

Before I was taking 30mg at 6am, 30mg at 11am, and 10-20mg at 3-4PM as needed.

I was never terribly regular with it. I didn't take notes or anything like that to determine when it was noticeable. Maybe I should have. I could definitely notice a "peak" of focus and concentration around 2 hours after I take the meds. Give or take.

So, I'm going to try to put together a spreadsheet to analyze the situation.

What I need is to understand how the meds dilute in my system over time.

I've found a few charts that give various examples of absorption curves. More would be nice.

I'm willing to open this up to other meds as well, if data is around. Nothing terribly hardcore is needed - this is more a thought exercise than a scientific tool.

The end result will be a way of determining:

a) When I should take which pills (ER or IR)
b) How many pills to take when

based on factors like:

a) Average amount in system desired
b) Maximum amount taken
c) Length of time to cover

and using parameters like:

a) eaten with food or not
b) personal scalars (some notice faster uptake, others slower)

Any thoughts?

I have a spreadsheet with some basics in it but I'm holding off on posting it for now.

You're going to have to help with some info: which medication?

Is it Ritalin, as per your signature?

Ritalin (racemic methylphenidate) has a plasma half-life of about 2 hours.
Dextroamphetamine has a half-life of 10 hours
Laevo-amphetamine has a half-life of 13 hours.
Adderall is 72% dextro, 28% laevo amphetamine.

As far as I know, while a drug is still in the plasma, it is still being supplied to the brain, since these drugs cross the blood/brain barrier. But obviously after 50% has been removed from blood, the effects in the brain aren't even likely to be noticeable.

Here's a more detailed study for blood/plasma levels of amphetamines for dextro-amphetamine: http://www3.interscience.wiley.com/cgi-bin/abstract/102531149/ABSTRACT?CRETRY=1&SRETRY=0

Interestingly, that study puts the peak plasma levels of amphetamine at about 3 hours, whilst many people put the length of time amphetamine works effectively in the brain also at 3 hours.

I don't understand a thing you said beyond you want to understand stuff about when people take pills and eat, or something. Make a questionaire and I'll fill it out.

I'm all for science, Bayashi, but I'm a moron. Remember that.

:D

You will also need to include other factors like physical activity.

I also wonder if other things will affect it, like food consumed, blood sugar, protein, available energy. Will the body rely more on the alleged stimulant affects of the drug?

Metabolic rate only really impacts the initial absorption rate of medications, not the the amount absorbed or length of time in brain/body/blood. And even then, not so much.

Fat stores, on the other hand, can alter things.

And as I've stated before, assuming you've a healthy individual, amino acids (protein) and glucose levels (carbs and sugar) do no affect ADHD.