Rigel says the inflammatory chemicals in cayenne pepper would make the skin swell over the muscles, giving the illusion of larger muscles. Yet with the cooling ingredients in Preparation H, and the obvious burning effect of cayenne pepper, men in clubs might choose to look small and sinewy rather than strong and swollen.
But Dr. Leslie Baumann, author of Skinguru.com and director of the Institute of Cosmetic Medicine and Research at the University of Miami, warns that Preparation H also can have uncomfortable side effects.
"It can work, but you can also get an allergy to it," said Baumann, who knew a friend who applied Preparation H under her eyes the day of her wedding only to break out with a rash on her face.
Rigel said Preparation H can have more serious side effects inside the body. Since the active ingredient works by constricting blood vessels, Preparation H has the potential to raise blood pressure.
"Probably if you put enough of it on, it would raise your blood pressure," Rigel said. "It's not designed to cover the whole area of your chest. It's designed to cover a small part of your rear end."