Propyl 4-Hydroxybenzoate

Products

Propyl 4-hydroxybenzoate (propylparaben) is used as an excipient in many drugs, especially in liquid and semisolid dosage forms.

Structure and properties

Propyl 4-hydroxybenzoate (C10H12O3, Mr = 180.2 g/mol) exists as a white crystalline powder and is very slightly soluble in water. The melting point is about 99 °C. Propyl 4-hydroxybenzoate belongs to the paraben group and is a propyl ester of -hydroxybenzoic acid. Also used is the more water-soluble sodium salt (E 217).

Effects

Propyl 4-hydroxybenzoate has antimicrobial properties against fungi and bacteria.

Indications for use

As a preservative for pharmaceuticals, foods and cosmetics.

Dosage

Propyl 4-hydroxybenzoate is also combined with other parabens and especially with methyl 4-hydroxybenzoate (methylparaben).

Adverse effects

Potential adverse effects include allergic reactions. Parabens are generally considered tolerable and have GRAS status, but they have a poor reputation among consumers.