Smelling salts have been used for centuries to keep people alert. They were once prominent in funeral homes and at blood drives. Athletes inhale them from the sidelines in hopes of improving performance. Rocky takes a whiff of a smelling salt to get back in the ring and continue the match. But how do these smelling salts work?
Smelling salts contain ammonia, a strong and foul-smelling chemical, said Dr Anthony Alessi (opens in a new tab)a clinical professor of neurology and orthopedics at the University of Connecticut.
The ammonia gas irritates the membranes in the nose and throughout the respiratory tract and causes an inhalation reflex, according to a 2006 study in British Journal of Sports Medicine (opens in a new tab). The inhalation reflex changes breathing patterns, increases oxygen flow and gas exchange, and can thus increase alertness in certain situations, the study authors wrote.
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While ammonia can be toxic if ingested in large amounts, a whiff of these salts is safe. However, that may not always be particularly helpful, Alessi said.
While it was once common to use smelling salts to keep athletes conscious after a concussion, this has fallen out of practice because it can be dangerous, Alessi said. It is a reflex to move away from a noxious smell; if an athlete has a head or neck injury, the sudden smell can cause them to flinch and aggravate the injury.
Athletes sometimes still use a whiff of smelling salts in an attempt to improve performance. Although the exercise may make them feel more alert and focused, there is no evidence that it actually improves muscle strength, according to a 2014 study in Journal of Exercise Physiology (opens in a new tab).
It is also important to note that if a person passes out or consciousness wavers, it is because the brain does not have everything it needs. It may lack energy or oxygen, so it starts over, Alessi said. This can happen in all kinds of situations, like when people pass out while watching gory movies or when people are with them diabetes fainting due to low blood sugar. In the past, people have rushed to smell salts because it feels like they are doing something about the loss of consciousness.
But in reality, fainting is often a protective mechanism that points to a larger problem that may need medical attention. So stopping it with smelling salts isn’t really a solution. “The brain is very resilient,” Allessi said, and it protects and revives itself.
This article is for informational purposes only and is not intended to provide medical advice.