A deodorant rash is a red, often itchy inflammation of the skin that occurs at the site of deodorant application. The vast majority of deodorant rashes are caused by skin sensitivity and allergic reactions. Friction and medical conditions like blocked sweat ducts can also contribute to deodorant rashes. People who sufferer from frequent or recurring armpit rashes often switch to all natural or hypoallergenic products, though rashes that do not disappear with time or new products must usually be treated by a medical doctor.

Deodorants are products designed to mask the smell of body odor emanating from the armpits. They are frequently combined with antiperspirants, which actually stop the flow of sweat in the first place. Both deodorants and antiperspirants contain a number of chemical compounds. They often contain fragrances, as well. Perfumes and chemical additives are the main culprits of a deodorant rash, particularly in people with sensitive skin.

Nearly all deodorant products on the market have undergone intensive testing to ensure that they are safe for contact with human skin. These tests usually only consider normal, healthy individuals, however. Sensitive skin and dry skin are not always taken into account.

Individuals with sensitive skin often find that they react negatively to one or more of the ingredients in their deodorant. More often than not, this sensitivity manifests itself as a rash. Switching to a product specially manufactured for sensitive skin often clears up the problem.

Allergies may also be at the root of a deodorant reaction. With allergies, the skin reacts not because it is irritated, but because its histamine triggers have been set off by some ingredient or additive in the deodorant. Histamines are part of the body’s immune response to foreign substances. People with allergies suffer from histamine firings when exposed to one or more generally harmless substances.

Treating an allergy-induced deodorant rash is very similar to treating one caused by skin sensitivity. Most of the time, finding a new deodorant — one that does not contain the allergen — is the best bet. Hypoallergenic deodorants will usually do the trick, though the only sure way for a person to discover the root cause of allergies is to visit an allergy specialist.

A deodorant rash can also be caused by application to broken skin. This most commonly occurs when people apply deodorant immediately after shaving their armpits, particularly if that shaving in any way nicked the skin. In this case, the rash is caused because the deodorant’s ingredients have penetrated into the body, resulting in irritation. These breakouts can generally be cleared up using a topical anti-itch or rash treatment cream, and the sufferer does not usually need to switch deodorants.

In rarer cases, a deodorant rash can be attributed to over-sweating, which can cause friction, or under-sweating, which can cause a heat rash. Both of these are sweat gland problems that are biologically based. Deodorant application exacerbates the rash but is not usually the actual cause of it.