SIGNIFICANCE OF A POSITIVE EPICUTANEOUS T EST TO LANOLIN

Significance of a Positive Epicutaneous Test to Lanolin Contact sensit izations to lanolin and its derivatives have received mention for some decades. Attempts to chemically identify the allergens in lanolin hav e failed. For this review, the frequency of allergy to lanolin and rel ated substances was studied by analyzing available data in the literat ure. Lanolin (anhydrous and hydrous) itself is a weak sensitizer. Most of the proven cases of contact sensitization to lanolin can be attrib uted to certain impurities. Sensitization is supposedly caused by resi dues in free alcohol-containing fraction of lanolin and traces of unre moved detergents. Infrequent contact sensitization to lanolin appears to depend to a large part on quality and purity of the raw material us ed. As shown in previous investigations, delayed-type reactions to lan olin were not reproducible in a large percentage of cases. Therefore, positive patch testing did not necessarily mean reactions upon practic al use in a given case. These observations indicate that the bad reput ation of lanolin as a common allergen should be reconsidered. In view of the benefits of lanolin as an excellent emulsifier and vehicle of i ngredients, more attention should be paid to the development of purifi ed lanolin preparations.