Propylene glycol
TYPE OF INGREDIENT
Humectant, emollient
COMMONLY FOUND IN
Creams, lotions, serums, washes
WHAT ARE THE BENEFITS OF PROPYLENE GLYCOL?
Propylene glycol has been shown to be a strong hygroscopic agent, allowing for moisture to penetrate the stratum corneum. In one study of 20 patients, propylene glycol 50% in water twice daily over 2 weeks improved tinea versicolor. It has been used in the delivery of medications, such as roflumilast or minoxidil.
WHAT IS PROPYLENE GLYCOL?
Propylene glycol is a humectant used as a vehicle to enhance penetration of other agents and molecules. It has hygroscopic properties, allowing it to be used to hydrate and carry other molecules to the skin in cosmetics and other personal care products.
IS PROPYLENE GLYCOL SAFE FOR ALL SKIN TYPES AND TONES?
Propylene glycol is likely safe for all skin types and tones; however, there are multiple reports of a dose-dependent allergic contact dermatitis or even systemic contact dermatitis related to it.
CONTRAINDICATIONS
A report on safety showed no significant contraindications for the use of products containing propylene glycol. However, there are significant reports of allergic contact dermatitis to it. Therefore, patients with allergic contact dermatitis should use products containing it with caution.
Sources:
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Cosmetic Ingredient Review Expert Panel. Final report on the safety assessment of methoxyisopropanol and methoxyisopropyl acetate as used in cosmetics. Int J Toxicol. 2008;27 Suppl 2:25-39.
Faergemann J, Fredriksson T. Propylene glycol in the treatment of tinea versicolor. Acta Derm Venereol. 1980;60(1):92-93.
Fiume MM, Bergfeld WF, Belsito DV, et al. Safety assessment of propylene glycol, tripropylene glycol, and PPGs as used in cosmetics. Int J Toxicol. 2012;31(5 Suppl):245S-60S.
Hernández N, Hernández Z, Liuti F, Borrego L. Intolerance to cosmetics as key to the diagnosis in a patient with allergic contact dermatitis caused by propylene glycol contained in a topical medication. Contact Dermatitis. 2017;76(4):246-247.
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Lowther A, McCormick T, Nedorost S. Systemic contact dermatitis from propylene glycol. Dermatitis. 2008;19(2):105-108.
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