In the presence of the skin’s natural moisture, aluminum chloride reacts with proteins and keratin inside the ducts. This forms tiny gel-like plugs that block the ducts and prevent sweat from reaching the skin’s surface.

With the ducts blocked, sweat from the treated glands is re-absorbed by surrounding tissue or evaporates deeper in the gland, instead of appearing on the skin.

Over the next several days, as your skin naturally sheds dead cells, these plugs break down and are released, after which normal sweating gradually resumes. That’s why protection can last 24 hours to several days, depending on your skin type and activity level.