The lanolin paradox.

Several puzzling aspects of the use of lanolin are discussed as "lanolin paradoxes', in analogy with the 'paraben paradoxes'. Lanolin in topical therapeutic agents sensitizes a high proportion of patients, whereas the same lanolin is 'safe' in cosmetics so widely used by millions of individuals. Patients with an allergic contact dermatitis to lanolin in a medication applied to a stasis ulcer can nevertheless use lanolin-containing cosmetics and not experience a reaction. Lanolin-sensitive individuals often show false-negative patch test reactions to unaltered lanolin. Patch testing with 30% wool wax alcohols used in the standard patch test tray cannot be considered a reliable method for detecting and confirming lanolin allergies. There are too many false-positive and false-negative results using the standard patch test tray.