Antiperspirants prevent odor and reduce sweat produced sweat glands. Antiperspirants - classified as drugs by the FDA - are typically applied to the underarms and attempt to stop or significantly reduce perspiration and thus reduce the moist climate in which bacteria thrive. Aluminum chloride, aluminum chlorohydrate, and aluminum zirconium compounds are the most widely used antiperspirants. Aluminium-based complexes react with the electrolytes in the sweat to form a gel plug in the duct of the sweat gland. The plugs prevent the gland from excreting liquid and are removed over time by the natural sloughing of the skin. Antiperspirants are often combined with deodorants which only reduce body odor but do not inhibit sweat. Deodorants like Zinc Ricinoleate do not reduce sweat production but only neutralize bad odors. Deodorants are not classified as OTC active ingredients.