Last week, the consumers not to buy or use "smelling salts" that are promoted to boost alertness and energy.
The agency said the products -- also known as ammonia inhalants -- are unapproved drugs and would need to be approved as any other over-the-counter (OTC) product for this particular use.
FDA also warned that inhaling ammonia "can quickly lead to coughing, airway constriction, and eye, nose, and throat irritation." It said it received reports of "shortness of breath, seizures, migraines, vomiting, diarrhea, and fainting from consumers after using these types of products, possibly purchased through various websites."
The FDA sent warning letters to several companies that make these products, which have names like Skull Smash and Nose Slap. its products "wake up the senses and deliver laser-like focus," while another its mint-scented product "is sure to get your attention, amp up your alertness and aggression, and deliver a punch."
Smelling salts have been in use for centuries, as a first-aid staple to revive the faint, or to revive athletes knocked unconscious, such as in boxing or hockey. But today, these smelling salts are marketed as a stimulant for athletic performance, sniffed out of packets or small containers on the sidelines or before lifting weights. Renewed interest may have come after an appearance on the and another .
The main ingredient in smelling salts can be ammonium carbonate, or diluted ammonia, water, and ethanol. The ammonia "provokes someone's nasal and lung membranes once they inhale through the nostrils. The end result is that the person involuntarily inhales and begins to respire quicker, which sends extra oxygen to the brain," according to one of the companies, .
But experts said it's still unclear whether or not smelling salts improve alertness, reaction time, or other elements of athletic performance -- and even their use in reviving unconscious athletes has been called into question by some experts.
"The internet has provided fertile ground for the revival of inhalants. Everyone should avoid these, especially those who have underlying neurologic conditions," said Anthony Alessi, MD, a neurologist and sports medicine specialist at the University of Connecticut.
Alessi about the potential harms of using smelling salts in patients with head trauma, noting that "the first response to the noxious smell is to suddenly jerk the head away from the stimulus. This can result in dislocating an injured spine and potential paralysis."
As for the potential side effects when used as an energy boost, the FDA Adverse Events Reporting System (FAERS) showed 26 related reports in 2023, up from just six in 2022. Only two, however, have been received for 2024. The cases largely cited nervous system, gastrointestinal, and respiratory disorders.
Lewis Nelson, MD, chief of medical toxicology at Rutgers New Jersey Medical School in Newark, told ѻý that he doubted that ammonia or ammonium carbonate itself could cause effects as serious as a seizure.
"If you were stuck in a room that was filled with ammonia gas, you would get lung toxicity, potentially you get airway injury, and you could potentially die," he said. "But breathing this stuff in a few times, or over a few hours, isn't really going to lead to any significant complications."
He added that the FDA warning is mostly "a regulatory issue ... about misbranding and mislabeling."