Medical Editor: Frederick Hecht, MD, F.A.A.P.
The first thing I always tell them is: "Contrary to what you've heard, eczema is rarely, if ever, caused by soaps and detergents."
I say this because it fits with my experience. People get rashes when they haven't used anything different, and they don't become consistently better if they keep shifting products in a futile effort to locate the culprit in the laundry.
And now -- at last! -- there is published scientific evidence to back up my experience.
In the Journal of the American Academy of Dermatology, Donald V. Belsito from the University of Kansas and his colleagues in the North American Contact Dermatitis Group published an article entitled "Allergic contact dermatitis to detergents: A multicenter study to assess prevalence." Their conclusion reads, in part: "Laundry detergents appear to be a rare cause of ACD [allergic contact dermatitis]." They found that fewer than 1% of patients, in whose cases a laundry product was suspected, reacted to allergy testing with detergent. The authors added that the true prevalence of allergy may have been even less than this small number since several patients who did react may simply have had an irritation rather than a true allergy.
No single study, however carefully done, ever settles a complicated issue once and for all. Still, it's gratifying to see science confirm clinical experience. Many cases of eczema reflect heredity or sensitivity rather than allergy. These rashes come and go as they please. Despite their unexplained onset and fluctuations, treatment can control them with little effort or risk.
So, before you chuck all your expensive soap, detergent, fabric softener, shampoo, or makeup, put conventional wisdom on hold and check with a physician to see whether what you're doing is helpful or just a waste of time and money.
Reference: Belsito, D. Journal of the American Academy of Dermatology; ""Allergic contact dermatitis to detergents: A multicenter study to assess prevalence." February 2002