Po
Polyaminopropyl Biguanide
Polyaminopropyl Biguanide · Polyhexamethylene Biguanide
A broad-spectrum preservative used at very low levels to protect a formula from microbes.
What it does
Polyaminopropyl Biguanide (PHMB) is a polymeric preservative effective against a broad range of bacteria and some fungi at very low concentrations. It disrupts microbial cell membranes, so it is used to keep water-containing formulas from spoiling. It is a preservation ingredient rather than a skin active.
Also known as
phmb, polyhexanide
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