All 4 Uses

adrenaline
in
The Guardian, by Nicholas Sparks
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You can shove that nod where the half-moons meet, Mike thought, feeling the adrenaline kick in again.†
Chpt 26 *

adrenaline = “fight or flight” stimulating hormone
Through the rush of adrenaline and frustration, he couldn't help but notice that as far as learning the ropes, Jennifer Romanello seemed to be a rather quick study.†
Chpt 34
As they moved farther into the distance, he could feel the adrenaline race into his system.†
Chpt 41
As he struggled to draw breath, he reached instinctively for Richard's hands, trying to pry them off as adrenaline began to surge.†
Chpt 42

Definitions:

(1) (adrenaline)
“fight or flight” stimulating hormone secreted by the adrenal gland in response to stress (making the body feel excited and ready for action)

Doctors are more likely to use the term epinephrine (possibly shortened to epi or EP). Adrenalin as a proper noun without the ending "e" is a trademark name for the same chemical.
(2) (meaning too rare to warrant focus)