It was almost midnight, and I was staring at the word oxybutynin like it had personally wronged me.

I had seen it maybe twenty times that week. Flashcard, missed. Practice question, missed. I knew it treated something with the bladder, I think, and that it blocked some receptor, and past that, my brain just went quiet. Around me, the library was clearing out. I had two hundred more drugs to learn, and Step 1 didn’t care how tired I was.

Here is the part nobody warns you about before med school. Pharmacology is not hard because the science is complicated. It is hard because there is so much of it, and it all sounds the same. Hundreds of names that blur together, each one dragging a mechanism, a receptor, and a list of side effects behind it. You do not understand your way through it. You memorize, and then you forget, and then you memorize again.

What scared me was not the workload. A classmate would rattle off what a drug did and how it worked, casually, like the facts were just sitting there within easy reach. I would nod along, go home, and lose another hour to a drug that just wouldn’t stick. And the thought I couldn’t shake was uglier than just falling behind: that everyone else had been right about themselves, and I had been wrong, that somewhere in the admissions process I had fooled people into believing I was something I wasn’t.

That night, too tired to do another flashcard, I did something dumb instead. I broke the word apart. Oxy. Butynin. Ox. Butting in. I pictured an actual ox shoving its way to the front of a waterslide, butting in, and blocking the water. That is what the drug does; it stops the flow. An overactive bladder, calmed down by an ox butting in. I never missed another oxybutynin question.

So I started doing it on purpose. I would take whatever drug was wrecking me that day and sit there until I found the story hiding inside its name. Pilocarpine turned into a pile o’ carp, wet and dripping with all its cholinergic effects. Colchicine turned into a piece of cold chicken, stiff and forgotten at the back of the freezer. My notebook filled up with these little scenes. They were silly, but they worked. For the first time, pharmacology felt less like a wall and more like a row of doors, and every door had a picture on it. The subject that made me question whether I belonged in med school became the one telling me I did.

I sent one to a classmate who was stuck on the same drug I had been stuck on. He sent it to someone else. A few days later, my phone buzzed with a text from a number I didn’t recognize: “Wait, that ox thing actually worked. Do you have more of these?” That was the moment it stopped being a private notebook.

By then, I knew the cost of being a medical student all too well. The resources everyone swears by are good, but expensive, and they stack up on top of a tuition that already keeps you awake at night. I had felt that math myself, sitting there deciding which study tools I could actually justify that month. These mnemonics had started as scraps I made to save myself, and putting them somewhere anyone could reach them felt like the only thing that made sense.

So that is what I did. One drug, one story, every Monday, open to whoever wants it. I built a free pharmacology resource where every drug gets a story-based mnemonic, so any student could use it. I figured a few friends might read it. Over a thousand students now get it in their inbox every week, and a few thousand more follow along. I still write every one of them at my desk, usually late at night when a new drug is giving me trouble.

I am not done with this story. I just started my third year, with a long way to go before anyone lets me call myself a doctor. But I have learned one thing I did not expect to learn in medical school. The thing that nearly breaks you is often the thing worth turning around and handing to the person behind you. Pharmacology almost beat me, and for a while, it made me think I didn’t belong here. Now, it is the reason some stranger out there remembers the right drug on a hard exam day.

And it all started with an ox, butting in, refusing to let anyone pass.

Matthew Tao is a medical student.