Why do some people get a metallic taste after the COVID vaccine?

metal taste after covid vaccine
Photo via Paulo O/Flickr (Public Domain)
  • This story is regularly updated for relevance. Last updated: July 19, 2021

The Centers for Disease Control and Prevention lists common side effects after getting a COVID-19 vaccine ranging from pain, redness, and swelling in the arm to flu-like symptoms such as fever, chills, tiredness, headaches, and muscle pains. However, a small number of people are experiencing a metal taste for hours, days, or even weeks after receiving the COVID vaccine.

NBC Sports contributor John Howard told NBC News that he equated the experience to “having nickels in your mouth.” Howard says that he noticed the metal taste “within minutes” after his first dose of the Pfizer COVID vaccine and that neither coffee nor mouthwash could thwart it.

“It’s certainly not debilitating or anything like that,” explained Howard. “But I do hope it goes away. I would like my coffee to taste normal.”

Dr. Buddy Creech, director of the Vanderbilt Vaccine Research Program in Nashville, said that he’s seen “a few individuals with unusual taste after vaccines.” He describes it as a “metallic taste that lasts for several days” but concedes that the effect is not considered to be dangerous and shouldn’t last long. And perhaps it’s not such a rare occurrence.

The infectious disease expert also stressed to NBC News that the metallic taste does not “indicate anything that would prevent getting the second dose of vaccine.”

Interestingly enough, this reaction isn’t even a new phenomenon. The side effect has popped up in other rare instances among people who have received vaccines, antibiotics, and pain medicines. One case report from 1999 even documented a woman who experienced a metallic taste after receiving a lidocaine injection, which is a type of anesthetic.

Though metallic is the most commonly reported taste, others with similar experiences have described it as salty, bitter, or rancid. It’s also not uncommon for people who are stricken with COVID to have strange tastebud sensations.

Nancy Rawson, the vice president of the Monell Chemical Senses Center in Philadelphia, told NBC News that the side effect is interesting because there doesn’t appear to be a biological basis for it. “There is no metallic taste receptor,” she said.

Or as John A. Sellick Jr., a professor of medicine at University at Buffalo-SUNY, theorized, “I suspect it’s part of a ‘vagal’ response—the same one that gives you sweats, flushing, and lightheadedness in anticipation of an injection [or] procedure.”

Given that people who become infected with COVID-19 sometimes experience changes or loss of taste and smell, Rawson says that it’s possible that people who notice a metallic taste were infected with the virus just before their vaccination. In either case, she recommends that people pay close attention to any symptoms or side effects in the week following their jab and seek medical attention if they persist.

In the meantime, Rawson suggests drinking a lot of water to help your saliva get back to its “optimal composition” and to “clear things out of your mouth.”

It’s also unclear exactly how many people have been affected by this unusual side effect. Out of thousands who described their experiences to AbScent, a nonprofit dedicated to smell disorders, only a handful of people reported a metallic taste after their vaccinations.

Dozens of people have also flocked to Reddit to compare notes with others who have noticed the metallic taste, but so far, there seems to be no consensus or explanation.

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Source: NBC News, National Library of Medicine, CDC

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