Pustolosi acuta localizzata da sodio metabisolfito

Adverse reactions to systemic drugs rarely may be due to vehicle components, such as preservatives, colorants and antioxidants. We report the case of a 44-year-old woman affected by localized pustulosis of the chin, neck and V of the chest, appeared after 2 days of intramuscular therapy with diclofenac. The patch test showed positive reaction to the drug as it and to sodium metabisulphite (5% pet). Sodium metabisulphite is an antioxidant mainly used in the food industry. However, it is present in some parenteral drugs, such as local anesthetics with adrenaline, diclofenac, and corticosteroids.