Secondary Logo

Journal Logo


The Worst Part of Waking Up

No Coffee in Your Cup

Walker, Graham MD

doi: 10.1097/01.EEM.0000469331.30378.99

Dr. Walkeris an emergency physician at Kaiser San Francisco. He is the developer and co-creator of MDCalc (, a medical calculator for clinical scores, equations, and risk stratifications, and The NNT (, a number-needed-to-treat tool to communicate benefit and harm. Follow him @grahamwalker, and read his past columns at






Coffee is not for me.

It's the drink some people wake up with.

That it makes them nervous is no myth.

Slaves to a coffee cup,

They can't give coffee up!

I thought of this song we sang in fourth grade as I went into my Cinco de Mayo overnight shift without my beloved brown energy drink. In fact, it was my first time without coffee in seven years of emergency department shifts.

My gastritis was at its worst in years. Despite taking my standard Prilosec and Pepcid, it was waking me up from sleep. I knew what any gastroenterologist would say to me, so I quit coffee cold turkey and cut alcohol from my diet, too. I acquired my caffeine instead from a variety of teas, and found a buzz from sugar and a lack of sleep. But I was worried. How would I function? Would I be a worse doctor? Would I fall asleep on my shift?

The answers: Just fine. I don't think so. The hours of 4-6 a.m. were rough, but I actually slept much better once I was home in bed.

Coffee is so completely tied to medicine for me that it was difficult to imagine hospital life without it. My father would drink it black before he drove into work at the hospital, and I started drinking it in medical school to stay up late memorizing microbiology parasites or to get up at 3:30 a.m. to pre-round on my surgery rotation. Amazing camaraderie is built into a team of doctors and nurses who are fighting a shared exhaustion by drinking coffee. I can't think of better bonding on my trauma rotation in Miami than going to the 24-hour Dunkin' Donuts for a disgustingly sweet cup of their iced joe.

Speaking of medical school, if you think back to those pharmacology days, you'll remember that caffeine is a xanthine that blocks adenosine, which helps you understand its effects. Adenosine induces drowsiness in the brain, so you block that and you stay awake. It also blocks adenosine in the kidney, too, causing diuresis and natriuresis in the proximal tubule. My least favorite side effect is the inhibition at the vagal nerve, which stimulates gastric ... motility. Its peak concentration is one to two hours after ingestion, and its first-order kinetics make some people have trouble sleeping with any caffeine after noon.

Legend has it that we can thank Ethiopian goat herders for their discovery of Coffea arabica's effects. They reportedly would see their herd start jumping after eating the plant's berries. The rest is history. Fast forward to modern day, and researchers estimate we now consume so much caffeine that it amounts to one serving of a caffeinated beverage for every person every day. (Interestingly, tea per weight has more caffeine in it, but tea is typically brewed not as strongly as coffee.)

Coffee gives me that perfect level of productive anxiety, that in-the-zone feeling where I'm on a roll, activating my thrusters and boosters and flying into overdrive during a busy ED shift. When six patients triage in 20 minutes, you take a big swig from your thermos and feel like you're moving as fast as the Flash. (There's even an app called “Caffeine Zone” to recommend how much and when to drink that second cup of coffee to maintain this high throughout the day.)

So how did the night shift — and the subsequent days — go?

Subsisting on tea just wasn't as enjoyable. I love me an Earl Grey or a Chai or a Matcha Green, but I just don't feel that surge of OVERWHELMING POWER coursing through my veins that I feel from a good cup of coffee. (And at my favorite brunch place? Forget about it. Give me coffee or give me death.) Tea gets me through the day or night shift, but I'm not particularly happy about it.

“We all have our vices,” an emergency physician once told me, “So I don't judge people when they come in with issues of their own.” I thought that was pretty good advice. Caffeine is clearly ours as physicians, emergency specialists especially. Giving up coffee hasn't been easy, but luckily I've been able to find some reasonable alternatives. Now, will someone fix my gastritis? I need my fix.

Share this article on Twitter and Facebook.

Access the links in EMN by reading this on our website or in our free iPad app, both available at

Comments? Write to us at

Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.