Pharmacology Through My Own Body — Closing Chapter. I Learned Pharmacology Again From My Own Body

When I studied pharmacology in medical school, drugs seemed fairly orderly.

Absorbed. Distributed. Metabolized. Excreted. Bound to a receptor. An effect appears.

It’s an accurate description.

But after living for years as a person with Parkinson’s disease, I found something missing between the lines of that description.

The human body.

The same drug did not produce the same result

The 100 mg written on the prescription is always 100 mg. But what the body made of it was not always the same.

Some days it was enough. Some days it was late. Some days it wasn’t enough. Some days it went too high.

For a long time I didn’t understand this difference. Then I came to understand it.

The drug is the input, and how the body moves is the output.

The same input does not always produce the same output.

Plasma concentration is the drug’s curve; output is the body’s curve

This sentence best captures the pharmacology I learned all over again.

The drug has its own curve. The body has its own curve. The two curves are connected, but they are not entirely the same.

Absorption. Gastric emptying. Meals. Sleep. Disease progression. The brain’s dopamine storage capacity. Motor state. All of this sits between the two curves.

In Part 1, I wrote that the patient stands between PK and PD. This record is what it looked like to live a day in that space between them.

My body is not a perfect laboratory

My data has many limitations.

It is not a randomized controlled trial. I did not measure plasma concentration. I could not fully control the conditions. The output scores I felt are subjective. And the sample size is small.

So this record cannot prove which drug is superior, or prove a treatment effect.

But that doesn’t mean it’s meaningless. Organizing a phenomenon that recurs in one person can be an important source of information for understanding that person’s course of treatment.

Personal data cannot replace a clinical trial. But a clinical trial cannot fully explain one individual’s day, either. The two are not competitors — they are different kinds of data that answer different questions.

The sentence I learned matters most

After years of recording my own body, the most important thing I learned turned out to be a surprisingly simple sentence.

Observed. Cause not yet known.

Once I could write that sentence, my records became a little more honest.

Dyskinesia appeared. That’s an observation. It was because of Ongentys. That’s a hypothesis.

The post-meal peak was late. That’s an observation. It was because of protein. That’s still a hypothesis.

The moment I separate the two, experience becomes a somewhat more scientific record.

Why I built the medication diary

The reason I built the medication diary comes down to that, in the end.

I didn’t set out to build a program that hands you the right answer. I wanted to build a tool that lets a patient see their own body more accurately.

Rather than forcing a choice between ON and OFF, I wanted people to be able to record how much they can move right now. What changed after taking the dose. When that change began. And what kind of curve it traced out over the day.

Accumulating records doesn’t produce every answer. But the questions get much better. I think that alone is a big enough change.

In the end, pharmacology was the study of a person meeting a drug

As I studied pharmacology again, what changed most was how I look at medication.

A drug is not simply a pill. It enters the body and creates time, builds a peak, falls, overlaps with the next dose, sometimes behaves as expected, and sometimes produces an entirely different result.

And all of that change happens inside one person’s day. The hour you want to walk. The hour you have to work. Mealtime. The time you fall asleep. The time you spend talking with family.

So I came to think that pharmacology is, in the end, the study of the moment a drug and a person meet.

Closing Words

This record does not mean that other patients should use the same drug the same way. It means the opposite.

The point of this piece is that even the same drug can produce different results from person to person — and different results from day to day in the same person.

So what matters is not following someone else’s prescription, but observing your own changes accurately and interpreting that record together with your care team.

The record of my own body isn’t the answer for everyone. But for me, at least, it was the first map that let me begin to understand what was happening in my own body.

I learned pharmacology as a physician. And after becoming a patient, I learned it again.

This time, not from a book,

I learned it with my own body.