NFL players will no longer be able to use smelling salts to get a quick jolt of alertness on the field. On Tuesday, the NFL announced the substance was banned for safety reasons.
The league cited a warning from the FDA released last year, informing consumers that smelling salts — often marketed to increase alertness and energy — have not been proven to be safe or effective for that purpose.
In addition to general safety concerns, the NFL noted the substance can mask symptoms of a concussion. Recent estimates suggest one concussion occurs every two NFL games.
San Francisco 49ers tight end George Kittle first revealed the ban in an interview with NFL Network on Tuesday, noting that he was "distraught" by the announcement because he uses smelling salts multiple times throughout a game and wanted to "figure out a middle ground" with the league. Other organizations, like the National Rugby League in Australia and International Boxing Federation, have banned the substance.
What are smelling salts?
Smelling salts are made of ammonium carbonate. When dried, the substance looks like table salt and was initially called the salt of hartshorn — named for the horns of male deer from which it was commonly derived in the 17th century. A liquid form of the substance was first used as a leavening agent before baking soda and powder became widely available.
Today, smelling salts and other ammonia inhalants are used to prevent and treat fainting. The Federal Aviation Administration even requires U.S. airlines to carry them onboard.
Once the ammonia is produced, it's packaged with water and other liquids into small, single-use capsules containing a few drops of the mixture. When the contents are crushed together, a chemical reaction releases ammonia gas and carbon dioxide.
"It's really gross. I mean, it smells really, really bad," Dr. Laura Boxley, a neuropsychologist at The Ohio State University Wexner Medical Center, said. "I think some people describe it as being like you're really close up to cat urine."
When inhaled, the ammonia gas activates receptors in the nose, which leads to a cascade of reactions that cause an increase in respiratory rate, cerebral blood flow and heart rate.
From the medicine cabinet to the field
But this physiological reaction has also been sought after by some athletes because it leads to a "subjective increase in perceived alertness and 'psyched-up energy,'" according to a recent paper about smelling salts.
"The use of smelling salts in sports is definitely not their intended use," Boxley said. "What's happening with some athletes is they're using them with much higher frequency than its intended use."
Smelling salts are widely available and can be purchased over the counter. Athletes like Tom Brady have used them in the past.
It's unclear when athletes first started using smelling salts, but Boxley compares their use to superstitious practices some athletes adopt.
"There's lots of things that athletes do, from a psychological perspective, that they feel gives them an edge," she said. "They are very famous for doing rituals like wearing a lucky shirt or wearing a certain hairdo."
Despite the perceived effects of smelling salts, there is no strong evidence to support the theory that smelling salts enhance athletic performance. Boxley added that some athletes who use smelling salts may link success on the field with their use of the substance.
"There is no performance benefit to ammonia inhalants in a short burst of maximal effort despite elevated arousal and an associated perception of performance enhancement," the authors of the same paper wrote.
Why sniffing for a boost could backfire
Though smelling salts are medically indicated at times, inappropriate and frequent use of the substance can lead to adverse events like shortness of breath, seizures and migraines. Even when these don't occur, the substance can still pose risks — especially in professional athletes.
When a football player has a concussion, symptoms usually include confusion, headache and dizziness. Using smelling salts can artificially elevate arousal levels, potentially masking these telltale signs.
If a player continues to use smelling salts after a concussion, it can worsen the injury. That's because the potent ammonia gas can trigger a sudden, automatic jolt of the head and neck.
"That certainly could complicate injury before it's been formally evaluated," Boxley explained.
Though smelling salts release a small amount of ammonia vapor, the long-term effects of repeated exposure are not well understood.
"Whenever you're using a tool outside of its recommended use, you're in kind of uncharted territory," Boxley said, noting that if players are willing to take that risk, the payoff should be worth it. "At the end of the day, he's not taking smelling salts to end world hunger, or prevent war. It's about whether or not he feels like he's doing his best on the next play."
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