Aluminium chloride

Aluminium chloride hexahydrate acts locally, in the stratum comeum and in the terminal duct, to relieve hyperhidrosis.

Aluminium chloride hexahydrate is acidic and is thought to act by diffusing into the sweat ducts where on neutralisation it forms gelatinous hydroxides which obstruct the flow of sweat.

The antiperspirant effect of aluminium chloride hexahydrate is partly explained by production of mechanical blockage in the eccrine sweat duct. Following application, aluminium is found in the stratum corneum and intra-luminally in the terminal duct.

It has been suggested that the metal ions form precipitating complexes with the mucopolysaccharides and carboxyl groups of the stratum corneum. This causes damage to the luminal epithelial cells, generating an obstructive conglomerate which plugs the acrosyringium. Studies of long-term treatment with aluminium chloride have shown that prolonged application leads to functional and structural degeneration of the eccrine acini, accounting for the observed progressive decrease in severity of hyperhidrosis during treatment.

Not applicable.

Absorption

Due to the effective absorption barriers of gut, lung and skin, the absorption rates of aluminium via the oral, inhalational and dermal routes are 0.1-0.3%, 1.5-2%, and approximately 0.01% respectively.

Distribution

About 90% of plasma aluminium is bound to transferrin, 7% occurs as citrate, and less than 1% as phosphate and hydroxide.

Elimination

More than 99% of orally ingested aluminium is eliminated via faeces. Of the small amounts of aluminium absorbed from the gastrointestinal tract, more than 95% is excreted in the urine.