sodium polymetaphosphate

sodium polymetaphosphate

astringent agent (see Table 1)
Table 1: Topical agents with astringent/anhidrotic action
AgentFormulation
AlcoholIMS; 70% isopropyl alcohol; spirituous lotions, e.g. 3% salicylic acid in IMS; surgical spirit; evaporates to cool skin and reduce maceration
Formalin10% solution causes a toughening effect on epidermis (may cause hypersensitivity)
AgNO320-25% solution (higher strengths can be used as NaCl in sweat mitigates the action of AgNO3)
Tannic acidAs dusting powder, or as borotannic complex giving an antifungal action
HamamelisWitch hazel: cooling effect
CalamineLotion or cream with a mild astringent and absorbent action; it will take up 1.5 times its own weight of water
Salicylic acid 3%Astringent and antiseptic as a lotion or dusting powder
Burow's solutionAluminium acetate ∼5% solution; diluted 1:3 in water to reduce sweat flow
TalcAntipruritic and absorbent; used as a base for dusting powders and to lubricate the skin
Dusting powdersAstringent medicament (e.g. tannic acid, salicylic acid), or antifungal medicament (e.g. boric acid, undecenoic acid) and lubricating applications in a talc, kaolin and/or zinc oxide base
OthersAgents that coincidentally show astringent/anhidrotic action include potassium permanganate, sodium polymetaphosphate, ferric chloride and compound tincture of benzoin

Note: Astringents act variously to cause protein precipitation (and thereby reduce epidermal maceration), cooling of tissues, constriction of sweat ducts and skin lubrication); anhidrotics act variously as cooling agents, astringents, and to alter epidermal reaction to retained sweat (e.g. reduce friction at the skin surface).

Both are used to control hyperhidrosis and bromidrosis by preventing the accumulation of sweat, increasing the skin's reaction to the action of sweat, and to compensate for any loss of resistance to infection at the skin surface.

IMS, industrial methylated spirit.