Ammonia and smelling salts have long been used as a stimulant by NFL players as well as other athletes, though the risks that come with their use have been noted. Many boxing competitions, for instance, have banned smelling salts under the pretense that their use can mask serious injury.

For years, NFL players - and athletes in other sports - routinely relied on smelling salts or ammonia capsules to jolt themselves awake on the sidelines. It was common to see playe