Allergic contact dermatitis from quaternium 15 in Oilatum cream.

Quaternium 15 is a formaldehyde releasing preservative with broad-spectrum activity against bacteria and to a lesser extent, yeasts and other fungi. It is widely used as a biocide in cosmetics and toiletries. Contact allergy to quanternium 15 is well recognized. Since 1982, researchers included this allergen in their standard patch test series and it is recommended in the standard series. Although quanternium 15 is not frequently used in medication but researchers were aware of its presence as a preservative in a moisturizing cream which is commonly used in Great Britain.