While reading for my board exams, I once again struggle with remembering which drug is used for which part of Horner's syndrome diagnosis. (Hey don't judge, I remember the concept but I really can't recall which name is associated with which..)

As you may know, one drug is used to confirm the diagnosis of Horner's syndrome, where instilling it into both eyes causes the anisocoria to be more pronounced. The other drug is used to determine where the defect is (3rd order neuron or before that). The two drugs are Cocaine and Amphetamine (yeah, crazy).

I just thought of a way to associate which is which properly.

Cocaine is like, crazy people right? So think pupils go even more bonkers, bigger goes even bigger smaller stays small. (This is because Cocaine blocks reuptake, so if there's any epinephrine there at the junction then it'll be more active, if there's none it will just stay the same).

While Amphetamine is like, for ADHD people (think Ritalin), increases focus, whatever. It is like "deeper". So it actually works by forcing the nerve release from the 3rd order neurons. If 3rd order neurons are dead then anisocoria won't reverse, if 3rd order neurons are ok then the miotic pupil will dilate.

That's just some tidbit I wanted to put out there.