Adrenaline is like fire.

Harness it, and it’s wonderful. But uncontrolled, it’s horrifying.

Adrenaline is that explosive hormone for flight or fight energy. It helps Marines charge that hill and marathoners make that final push. I’ve heard a story of a small young mother who found superhuman strength to stop a rolling car from running crushing her infant. Adrenaline.

It can be addictive, as any emergency room doctor will tell you. Stabbings and gunshot wounds were the staple of my surgical rotation in medical school in the Bronx. Adrenaline fueled the energy to keep the doctors awake and the trauma patients alive — and momentarily made everything else irrelevant, like the brain stain on my right shoe, the result of a patient with a gunshot to the head. I had those shoes, with that stain, until about five years ago.

How many on-call nights were shattered by the “code pager” blaring that there was a cardiac arrest to run to — an adrenaline-fueled sprint. At my first code, pulse pounding, tunnel vision, it felt impossible to breathe, much less act. My resident gave me the age-old advice told to interns since the beginning of medicine: “First thing in a code is to take your own pulse.” It seemed like ridiculous advice at first. But when I did it, it focused me and let the adrenaline work in my favor.

Just give a bit too much adrenaline to someone when they don’t want it, and it is a full-blown panic attack. I remember deciding to apply to medical schools, so I called the admissions director at UConn. When he came to the line, I suddenly had this irrational fear that this call would ruin my chances of any future. My heart raced, my eyesight went black, I couldn’t breathe, much less speak. It was all I could do to say, “Hold on a moment,” while I caught my breath, regained composure, and was able to speak, not entirely intelligibly, but at least I could talk.

Adrenaline-fueled panic has happened in all the usual times in my life, like right before I asked a pretty girl named Gretchen to my eighth grade semiformal dance. She said yes, anyway (probably out of pity, or because no one else asked her). But such panic has also cropped up at the most unexpected and unwanted times in my life.

Once I had to call a surgeon I knew well and liked to tell him that the patient I referred to him for surgery had not wanted to see him and then had said some horribly offensive things about the surgeon. For some reason, this made me so anxious, I felt that inexplicable panic feeling when I called the surgeon, even though I didn’t tell him why the patient chose another surgeon.

I know people who are smart, attractive, funny and clever who become incapacitated with panic attacks in the most seemingly benign social situations. And while it’s intellectually fascinating to think of the storm of adrenaline surging in the body, causing dry mouth, fast breathing, heart racing, tunnel vision or no vision, the physiologic process ranks among the worst of all feelings — and I can personally attest that this is true. Which brings me back to the lesson told to me by my resident: The first thing to do is to take your own pulse.