Lanolin, identified primarily for its emollient properties, has been named by the American Contact Dermatitis Society because the Contact Allergen of the 12 months for 2023.
Lanolin is a posh and ranging combination of excessive molecular weight esters, aliphatic alcohols, sterols, fatty acids, and hydrocarbons, however the allergic parts are primarily the free lanolin alcohols, particularly alkanediols, mentioned Donald V. Belsito, MD, professor of dermatology, Columbia College, New York, who introduced the Allergen of the 12 months on the society’s annual assembly.
Standards for choice can embody a identified allergen with a brand new twist or rising frequency or a newly reported allergen with mini-epidemics which will have been missed for years, Belsito mentioned.
“The prevalence and severity of allergy to ‘lanolin’ have been hotly debated” since a possible case was first reported within the Nineteen Twenties, wrote Belsito and Blair A. Jenkins, MD, PhD, a dermatology resident at New York–Presbyterian Hospital, Columbia Campus, in a overview printed in Dermatitis.
“ ’Lanolin’ is certainly a paradox allergen,” wrote Jenkins and Belsito. “Probably the most acceptable patch take a look at preparation(s) for detecting allergy stay disputed. Detection of lanolin-induced contact dermatitis in diseased pores and skin by patch testing on regular pores and skin could result in false unfavourable outcomes.”
And those that take a look at constructive for a lanolin allergy on diseased pores and skin could possibly use lanolin merchandise on regular pores and skin, they wrote.
“From my perspective, this was a well timed 12 months to consider lanolin, as there may be important ongoing controversy about whether or not it’s allergenic,” Jenkins mentioned in an interview. “Quite a few firms market lanolin-containing topicals as protected and efficient emollients,” she mentioned.
Medical grade and extremely purified anhydrous lanolin, which comprise lower than 2.5% and fewer than 1.5% of free alcohols, respectively, can nonetheless elicit or induce a contact allergy, Belsito mentioned in his presentation. Hydrogenated lanolin has proven extra allergenicity than lanolin alcohol, whereas lanolin wax, lanolin acid, and lanolin esters possess decrease allergenicity than lanolin alcohol, he mentioned.
Notably, trendy wool textiles don’t comprise lanolin, and lanolin-allergic sufferers needn’t keep away from wool, Belsito added.
Amerchol L-101, a standard commerce title on merchandise containing lanolin, comprises 10% wool wax alcohols obtained from the hydrolysis of wool fats dissolved in mineral oil at a 1:1 ratio, mentioned Belsito. He really useful testing lanolin alcohols (in 30% petrolatum) and Amerchol L-101 (in 50% petrolatum) concurrently with or with out different lanolin derivatives and/or the affected person’s merchandise in instances of doable allergy, he mentioned.
Think about Excessive-Danger Teams
Present proof means that the prevalence of contact allergy within the western European inhabitants is 0.4%, wrote Jenkins and Belsito.
Though the frequency of lanolin allergy is comparatively low, sure circumstances convey better threat, equivalent to stasis dermatitis, leg ulcers, perianal/genital dermatitis, and atopic dermatitis, they wrote. Older adults and kids are at elevated threat as a result of they’re extra more likely to have these circumstances. Demographic information additionally recommend that lanolin allergy is extra widespread in non-Hispanic Whites than in non-Hispanic Blacks, they wrote.
Wanting forward, “I believe additional exploration of allergy throughout completely different pores and skin varieties and ethnicities is warranted,” Jenkins mentioned. “Additional investigation of ideally suited [lanolin] allergens for patch testing can also be wanted.”
Jenkins and Belsito mentioned they’d no related monetary conflicts to reveal.
This story initially appeared on MDedge.com, a part of the Medscape Skilled Community.