BACKGROUND: Lanolin has been tested as lanolin alcohols (30% pet.) in baseline patch test series since 1969, and this has shown clinically relevant allergic contact dermatitis cases.

OBJECTIVES: To investigate the temporal development of lanolin allergy (i.e. positive reaction to lanolin alcohols and/or Amerchol™ L-101), and the association between contact allergy to lanolin and patient characteristics from the MOAHLFA index.

METHODS: A retrospective observational study of consecutively patch tested dermatitis patients (n = 9577) between 1 January 2004 and 31 December 2015 with lanolin alcohols 30% pet. and Amerchol™ L-101 50% pet. was performed.

RESULTS: The prevalence of lanolin allergy increased from 0.45% in 2004 to 1.81% in 2015. In age-adjusted and sex-adjusted analyses, weak, significant associations were found between atopic dermatitis and lanolin and lanolin alcohols allergy, respectively, but no association with Amerchol™ L-101 allergy was found. Among 9286 dermatitis patients who were tested with both allergens, 108 had a positive test reaction to either lanolin alcohols or Amerchol™ L-101, whereas only 29 patients had positive test reactions to both markers.

CONCLUSIONS: The prevalence of lanolin contact allergy has increased over a 12-year period, and inclusion of Amerchol™ L-101 will increase the chance of detecting lanolin contact allergy. Patch testing with lanolin is helpful in atopics with dermatitis and suspected cosmetic allergy.