Common skin care ingredients -- P

PABA (Para-Aminobenzoic Acid): UVB blocker used in sunscreens during the 1970's; can cause contact dermatitis, therefore is now out of favor.

Panthenol: a B vitamin (B5), works as a humectant (holds water in the skin). May promote skin healing.

Parabens: One of the most commonly used group of preservatives in cosmetics today; nonirritating and nonsensitizing. Methyl paraben may degrade releasing methanol, a potentially toxic chemical. To what degree this actualy occurs in skin care products is unclear. Various forms exist, name ending in (e.g. methyl paraben, ethyl paraben, etc.).

Petrolatum: Heavy vehicle based on petroleum hydrocarbons, most commonly known for its use in Vaseline; good for sensitive skin but is occlusive and can cause or aggravate acne in susceptible individuals.

Polybutene: helps make liquids texturally viscous.

Poly Hydroxy Acid: PHA, derived from the buds of fruit trees; is claimed to be gentler yet as effective as AHAs; still debatable.

Proline: amino acid vital to the composition and production collagen; possibly ineffective in topical products.

Propylene Glycol: vehicle for cosmetic solutions; excellent for hydrating dry skin but can act as a contact dermatitis sensitizer in susceptible individuals.