183 Efficacy of Petrolatum VPJ has been found useful in multiple skin-healing applications. PJ is considered a moisturizer with therapeutic attributes because it creates a highly occlusive, semipermeable barrier that allows for exchange of water and oxygen. This contrasts with the application of higher occlusion products, such as certain polymers, that likely impair barrier function (25,15). These examples establish petrolatum as a safe and effective wound care agent, with a similarly low infection rate and minimal risk for inducing allergies. OTHER APPLICATIONS PF is not just restricted to leave-on care applications. It has also been tested in cleansing formulations for mildness benefits. In a clinical trial involving subjects with moderate xerotic eczema, those using a petrolatum-delivering bodywash demonstrated enhanced clinical benefits over conventional cleansing systems (70). Furthermore, in a study involving subjects with moderately dry legs, use of a petrolatum-containing bodywash had positive benefits on stratum corneum health, such as hydration and biomarkers including improved cohesion as measured by tape stripping (71). Petrolatum has also been used as an emollient in hair care to coat the hair fibers, thus repelling water loss and maintaining style integrity. Additionally, pomades consisting of petrolatum are applied directly to the scalp, typically before harsher treatments—such as chemical hair straighteners—to mitigate irritation (72). CONCLUSION Petrolatum has been shown to be safe and effective for topical use and by ingestion. Its long history of use and extensive testing have demonstrated that it is nonirritating, is hypoallergenic, and has no systemic toxicity. Petrolatum is also highly efficacious in the treatment of barrier impairment and wound healing. Multiple studies have compared petrolatum’s therapeutic potential to a wide assortment of other ointments, moisturizers, and oils, including those containing antibiotics or other drugs. In many of these comparisons, petrolatum was found to be comparable or superior to the other ointments and oils. Furthermore, petrolatum is highly cost-effective when compared to steroid-, calcineurin-, and antibiotic-containing ointments. Petrolatum may have some unique advantages compared with other moisturizers, because it has been shown to accelerate the skin’s own barrier repair mechanisms and to stimulate aspects of the innate immune response, such as production of AMPs. Robert Chesebrough’s description of PJ as a “wonder jelly” still rings true to this day. REFERENCES (1) R.A. Cheseborough, Improvement in products from petroleum. US patent 127,568. June 4, 1872. (2) Unilever Vaseline, The Healing Power of Vaseline®, accessed May 16, 2022, http://www.vaseline.co.uk/ article/vaselinestory.html. (3) P. Homan, Vaseline: from trad mark to noun, Pharm. J. (2008). (4) K.M. Al Aboud and A. Khachemoune, Vaseline: a historical perspective, Dermatol. Nurs., 21, 143–144 (2009). (5) B.W. Barry and A.J. Grace, Structural, rheological and textural properties of soft paraffins, J. Texture Stud., 2, 259–279 (1971).

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