A deodorant is a substance applied to the body to prevent body odor caused by the bacterial breakdown of perspiration in armpits, feet, and other areas of the body. A subgroup of deodorants, antiperspirants, affect odor as well as prevent sweating by affecting sweat glands.
Antiperspirants are typically applied to the underarms, while deodorants may also be used on feet and other areas in the form of body sprays. Aerosol antiperspirant products may, however, be applied to non-underarm body areas where excessive sweating (hyperhidrosis) is a problem. Aerosol antiperspirants may be particularly helpful to control sweat on the feet. It's recommended that a person try the antiperspirant on a small area of the skin first, to make sure that he/she does not have a reaction to it.