Background: Most studies investigating steroid allergy have been performed with tixocortol pivalate, hydrocortisone butyrate and budesonide. Betnovate and Dermovate are widely prescribed in the U.K. but little is known about the frequency of sensitization to them.
Objectives: To determine the optimum method to detect contact allergy to betamethasone valerate (BV) and clobetasol propionate (CP).
Methods: Seven centres tested consecutive patients attending for investigation of suspected allergic contact dermatitis to these steroids at a range of concentrations in different vehicles.
Results: Of 1562 patients tested, 16 (1%) reacted to either BV or CP. Ten patients (0.7%) reacted to BV and 13 (0.8%) to CP. Two patients of a further centre were included in analysis of dilutions and vehicles. Sixteen of a total of 25 reactions (64%) were identified with a 1% dilution in ethanol.
Conclusions: Consideration should be given to adding BV and CP to a standard allergy series, given that both are frequently used in the treatment of eczema and that most patients sensitized to them are not identified with currently used markers of steroid allergy. If patch tests to BV and CP are initially negative, but an allergy is suspected, the patient should be further investigated. Further studies are required to identify the ideal patch test material.