Allergic contact dermatitis caused by dexpanthenol-Probably a frequent allergen

Panthenol (synonym: dexpanthenol), the alcohol analogue of panthothenic acid, is frequently included in moisturizers, wound-healing agents, and other cosmetics, and has been shown to be responsible for allergic contact dermatitis (ACD).

To evaluate the frequency of ACD caused by dexpanthenol, and to characterize reactive patients.

We retrospectively reviewed the files of patients patch tested between 2009 and 2017 in the Department of Dermatology of the Coimbra's University Hospital and describe patients who reacted to dexpanthenol 5% pet., tested initially in a cosmetic/vehicle series and in the last 3 years in consecutive patients.

Among 2171 patients, 26 (1.2%) had positive patch test reactions to dexpanthenol, mostly patients tested for chronic eczema (88.5%, n = 23), either widespread (5), or localized to the hands (5), face (4), or legs (7). Relevance could be traced in 20 patients (76.9%), related to the use of Bepanthene cream (15), moisturizers (3), topical medications (1), and a shampoo (1). Twenty-five of 26 patients (96.2%) reacted to several other allergens, mostly ingredients of cosmetic or pharmaceutical products.

Although ACD caused by dexpanthenol is considered to be rare, it may be frequently overlooked. As we found a relatively high frequency of relevant cases, in agreement with a previous study, the inclusion of dexpanthenol in patch test series, at least in cosmetic and topical drug series, is encouraged.