Grin and Bear It: Why Smiling Makes Vaccine Shots Less Painful

By Pat Anson, PNN Editor

Over the next few months, tens of millions of people around the world will be getting the first injections of COVID-19 vaccines, with some getting a vaccine that requires two shots to be effective.

Whether it’s a shot for the flu, pneumonia, shingles or COVID, no one looks forward to stabbing pain from the oversized needles often used in vaccinations. Is there anything you can do to help relieve the sting from a needle prick?

An unusual study led by researchers at the University of California, Irvine, found an unexpected way to dull the pain: Put a big smile on your face.

Researchers say that a broad smile -- one that elevates the corners of the mouth and creates crow's feet around the eyes -- can reduce the pain of a needle injection by as much as 40 percent. That genuine smile, known as a Duchenne smile, can also lower your stress and heart rate during a needle injection.

If you find the idea of smiling during an injection a little silly, then feel free to grimace instead. Grimacing uses the same facial muscles as smiling and is just as effective at pain relief, according to researchers.

"When facing distress or pleasure, humans make remarkably similar facial expressions that involve activation of the eye muscles, lifting of the cheeks and baring of the teeth," says lead investigator Sarah Pressman, PhD, a professor of psychological science at UCI. "We found that these movements, as opposed to a neutral expression, are beneficial in reducing discomfort and stress."

To test their theory, Pressman and her colleagues found 231 healthy volunteers who self-reported their levels of pain, emotion and distress while being injected in the upper arm with saline from a 25-gauge needle — the type often used in a flu shot.

Before and during the injection, participants were randomly selected to use either a Duchenne smile, a small smile, a grimace or a neutral expression. All four facial expressions were facilitated by holding chopsticks in their teeth.

Those in the Duchenne smile and grimace groups reported 40% and 39% less pain, respectively, during the injection than the neutral group, while participants in the small smile group had 26% less pain.

The Duchenne smile and grimace groups (images C and D) were also associated with slightly lower stress and heart rates.

“Why did these two disparate expressions perform so similarly? As discussed previously, this overlap could be explained by the fact that similar muscle groups are activated in both expressions,” researchers reported in the journal Emotion.

“Grimacing has long been used as a nonverbal indicator of pain and has been manipulated unintentionally via common medical practices from the Middle Ages that tell individuals to ‘bite down’ on pieces of wood and leather during painful procedures. To our knowledge, this is the first experimental test showing that this natural response to pain is helpful in improving the subjective pain experience.”

The researchers aren’t suggesting a return to the Middle Ages or that you bite down on chopsticks the next time you’re vaccinated. But they do think that “device-in-mouth manipulation” and “creative paradigms to manipulate facial expressions” are worthy of future pain research.     

"Our study demonstrates a simple, free and clinically meaningful method of making the needle injection less awful," Pressman said. "Given the numerous anxiety- and pain-provoking situations found in medical practice, we hope that an understanding of how and when smiling and grimacing helps will foster effective pain reduction strategies that result in better patient experiences."

Wear, Tear & Care: Needling Away Pain

By Jennifer Kain Kilgore, Columnist

One would think that encouraging inflammation is a bad idea, right?

“Let’s stick you with needles, inject a dextrose solution, and create some new tissue. It’ll be great!”

That’s what my dad has been saying since 2004. He had prolotherapy done for his low back in college, and it did wonders for him. I was extremely dubious. It sounded far too strange – injecting a sugar solution? Into my neck?

I have very extensive injuries from two separate car accidents. To sum it up quickly, I have badly-healed thoracic fractures, bulging lumbar discs hitting nerves, and two cervical fusions that cause a lot of post-surgical pain. The idea of purposefully creating more inflammation sounded insane. But after my second fusion, when the pain started increasing no matter how dutifully it was treated, I decided to give it a try.

Prolotherapy, or sclerosing injections, is still considered a bit radical, even though it’s been around since the 1930’s. The reason for the mystery is because there haven’t been enough double-blind studies conducted yet.

It’s a non-surgical ligament and tendon reconstruction injection designed to stimulate the body’s natural healing processes. By creating inflammation, you prod the body to create new collagen tissue and help weak connective tissue become stronger.

Because I live in the Boston area, that meant the drive to the doctor’s office was an hour each way. Most people do each area (lumbar, thoracic, cervical) separately, and each area takes approximately five rounds of shots. For me, that would’ve meant an eternity of needles.

I chose the insane route: five weeks of intense pain, meaning five weeks of all three areas at the same time.

It’s not supposed to hurt that much – people can take an aspirin and go to work after the appointment, grumbling about their aching knee. My pain response has become far more sensitive in my back and neck since the accidents, so what’s like a bee sting for other people is like thick surgical needles for me.

As such, it was hellishly difficult. Each appointment was on a Wednesday and took about fifteen minutes. The doctor injected my low back and then let me rest with an ice pack down the back of my pants. Then he injected my neck, loading me with more ice packs. Then, very gingerly, he approached the mid-back, which was the most damaged of all. He had to consult my MRIs for that one because the bones are not quite where they’re supposed to be.

For me, it took about an hour for the real pain to kick in, which gave me just enough time to drive home. The doctor numbed me with a topical anesthetic as well, so I sat on five ice packs and made the drive back to my house, where I collected all the ice packs in the freezer and arranged them on the recliner. Then I wouldn’t move for about two days. Sleeping was almost impossible without ice packs stuffed into my pajamas; I still can’t sleep on my back, two months later. Sitting like a normal human being was out of the question.

For five weeks, I spent the two or three days after shots recovering from absurd amounts of pain, and then by the time I’d recovered, it was almost time for the next round. My level of pain was far more than what other people online have reported. I also did a lot more shots at once than other people do. My experience was very much abnormal. But, most importantly: Did it work?

Well, yes. It did. Amazingly so. I’d told myself at the beginning that if this procedure controlled even 25 percent of the pain, that would be worth it. That would be worth the driving, the pain, and the out-of-pocket cost that isn’t covered by insurance.

My cervical fusions caused my arms not to work a lot of the time. Typing, writing, and using my hands for general tasks was very difficult and tiring. Additionally, my shoulder blades had what felt like black holes filled with electric fire. Nothing helped it. Nothing worked.

Two weeks into the prolotherapy regimen, my arms were fine and the black holes had disappeared.

I still have a lot of my daily low-grade, all-body pain. I still have massive headaches and neck pain. But my sciatica is also better, I’ve noticed – I was able to go to a rock park called Purgatory Chasm and clamber all over humongous boulders, and afterward I was only sore, not in agony.

So do I think it works? Absolutely. The other great part is that it’s supposed to last for at least a few years. Steroid injections only last a few months. I very much prefer this schedule.

If you can get past the “alternative therapy” label and can scrounge up the money to pay for it, I’d highly recommend prolotherapy. It worked for me, and I’m still waiting to see more of its effects. I hope that it works as well for you.

Jennifer Kain Kilgore is an attorney in the Greater Boston area who also works as a writer and editor in her spare time.  She has chronic back and neck pain after two car accidents.

You can read more about Jennifer on her blog, Wear, Tear, & Care.  

The information in this column should not be considered as professional medical advice, diagnosis or treatment. It is for informational purposes only and represents the author’s opinions alone. It does not inherently express or reflect the views, opinions and/or positions of Pain News Network.