Semisolid paraffin, otherwise known as vaseline, and liquid paraffin, or vaseline oil, are petroleum based. Soft paraffin, sterile white paraffin in particular, is used to treat some wounds and lesions such as burns, chiefly for its softening and moisturising effect (emollient) and as a lubricant. It is sometimes applied to the eye in the form of ophthalmic preparations to treat ocular dryness. Liquid paraffin, alone or in combination, is also used in these various indications.
Paraffin and paraffin-impregnated dressings applied to burns and other lesions expose the patient to few adverse effects, the main one being acne. Hypersensitivity reactions are associated with impurities, but this risk is reduced by using white soft paraffin, which is purified. Lung damage (lipoid pneumonia) has been reported when soft paraffin is applied regularly to the face or in the nose, as a result of involuntary inhalation of liquid paraffin or its use in nasal solutions. No particular risk of cancer has been signalled resulting from the use of purified forms of soft paraffin or of liquid paraffin for therapeutic purposes.
As with any greasy substance, the application of soft paraffin on the face and hands of patients on oxygen should be avoided, due to the risk of ignition or combustion in the event of proximity to a flame or spark.
In practice, mid-2013, soft paraffin is the reference emollient, because it exposes patients to few adverse effects.
©Prescrire 1 November 2013
"Queries and comments. Soft paraffin: what are the risks?" Prescrire Int 2013; 22 (143): 279. (Pdf, subscribers only).