Henna is a vegetable dye that comes in brown, red or green colors and wears off in a few days. Henna tattoos are widely available and harmless most of the time.

In an effort to produce darker effects of the henna tattoos, tattoo artists have to add a chemical called para-phenylenediamine, or PPD which has been found to cause powerful allergic reactions. FDA report says that the only legal use for PPD is as a hair dye.

A 19 year-old girl who had a henna tattoo done on her hand eight days before her wedding developed blisters following the tattooing event. She had to be treated with topical corticosteroids but the blisters persisted for over a week. Additionally, the blistering left behind a dark pigmentation that will take six months or more to disappear.

There’s a question if henna without PPD was any safer since there have been reports of allergy to henna itself, quite rare though. On the other hand, allergy to PPD is extremely common.

The American Academy of Dermatology (AAD) warns of the PPD additive in black henna inks that has been found to put the wearers at risk for a number of skin conditions such as allergic dermatitis, eczema, scarring.
Black henna tattoos are widely available especially at the summer carnivals, open-air malls, vacation spots, and cruise ships. PPD is sometimes even added to natural henna to increase its intensity and longevity.

Although the FDA prohibits the direct application of PPD to the skin there are no regulations in the tattoo industry and more and more consumers are getting black henna tattoos, putting themselves at risk for serious skin problems.

There is an increase in the number of children having henna tattoos done, even children as young as four, many of which are experiencing skin reactions. The problem lies in the parents’ ignorance. They believe hennas are safe since they are not permanent and since they are so widely available. However, nothing could be further from the truth.
The experienced skin reactions differ in severity and range from mild eczema to blistering and permanent scarring. Topical steroids do help with some of the allergy symptoms.

Health experts say that one exposure to the PPD could lead to a lifelong sensitivity or cause cross reaction to other compounds, including certain medications. They advise that people looking for a henna tattoo should go for the traditional vegetable-based, reddish-brown in color and to avoid those that are PPD-adulterated.