Public Health – Seattle & King County is warning against use of henna products that contain additives to create temporary tattoos. Materials that are sometimes added to henna can cause allergic reactions in some people when applied to the skin, and cause people to develop lasting chemical sensitivities. One of the most commonly used additives and one that is of particular concern is paraphenylenediamine (PPD). PPD is used as a darkening agent to create “black henna”. PPD is approved by the U.S. Food and Drug Administration (FDA) for use in hair dye, but not in cosmetics that are applied directly to the skin. It is known to cause allergic skin reactions in some people, resulting in intense itching, redness of the skin, blistering, infections, and – in some cases -permanent scarring. In some individuals, the scarring can be accompanied by light or dark patches on the skin. In addition, an allergic reaction to PPD in a henna product used on the skin can set the stage for allergic responses to similar chemicals later on, including ingredients in hair dye, sunscreen and medications.
Pure henna is a red or brown dye derived from the dried leaves of the henna shrub, and commonly used as a hair coloring agent. Although not approved by FDA for direct application to the skin, henna is commonly used for temporary tattoos. Allergic reactions from use of pure henna on the skin have rarely been reported.