Irritant thresholds in subjects with colophony allergy

The factors which determine individual susceptibility to the development of allergic contact dermatitis (ACD) are not well defined. Since it is known that the presence of skin irritation is well-documented as a promoter of se nsitization, the sensitivity to irritation of subjects with ACD has been co mpared with a normal control group. Whilst 78% of those with a positive pat ch test reaction to the contact allergen colophony (colophonium) responded to a concentration of no higher than 2.5% sodium lauryl sulfate (SLS), only 44% of the matched control group reacted at this level of SLS. Thus, the r esults are consistent with the hypothesis that individuals with enhanced su sceptibility to skin irritation are also more liable to develop allergic sk in reactivity.