Why do henna tattoos itch

Henna tattoos - beautiful, but not harmless

Sun, palm trees, beach - who wouldn't want to look something exotic or sexy? And so more and more vacationers decorate their tanned skin on the upper arm, shoulder blade, wrist, stomach or feet with a henna tattoo.

Admittedly, the artistic motifs that are applied to the skin by hawkers on the beach, on busy streets and squares with a henna solution look great.

And in contrast to real tattoos, the so-called Temptattoos have the advantage that they fade within a short time until they finally disappear again without a trace. Because the natural product henna only colors the top layer of skin - the epidermis - which is constantly renewed.

Harmless ornament?

Actually a nice and harmless thing. Not always, however, because sometimes the skin resents the "beautification action" and reacts allergically. In Zurich's Triemli Spital alone, the doctors had to treat 15 patients with contact eczema from the supposedly harmless henna tattoos within three months.

Around 53 such cases have already been reported in the medical press. According to experts, this is only the tip of an iceberg reaching far below.

Beware of "black" henna

Henna is an extract obtained from the leaves of the Egyptian dye bush Lawsonia inermis and has been used for thousands of years to dye hair, nails and skin - the best known are the hand and foot paintings of Indian brides. Applied in a highly concentrated manner to the skin and with a long exposure time - between three to eight hours - it turns orange to brown, depending on the skin type.

In order to make the colors in the skin appear darker and stronger, to achieve an effective blackening or to shorten the exposure time, other pigments are added to the "henna ink". The most popular substance is para-phenylenediamine (PPD). It is often found in what is known as "black" henna. Para-phenylenediamine is a contact allergen that can cause severe to very severe skin reactions and damage that can last for years, sometimes decades.

Itching usually comes after the vacation

Within 14 days - so often only after returning and when the holiday souvenir has already faded - there is excruciating itching, severe swelling and redness at the point where the supposedly harmless tattoo was. A visit to the dermatologist or allergist becomes inevitable so that the area can be treated professionally. From a certain inflammation intensity, flat scars remain in the form of light spots - the specialist speaks of hypopigmentation.

In most cases that is not enough. The allergic reaction to para-phenylenediamine has far more far-reaching consequences for those affected. Because contact with related substances such as p-tolylenediamine, p-aminoazobenzene, 4-aminophenol and 3-aminophenol often leads to allergic reactions.

Late consequences: restricted choice of profession

For example, the tattoo, which is actually intended as a harmless holiday pleasure, can lead to the choice of career being restricted. Because with a para-phenylenediamine contact allergy, professions such as hairdresser, printer, shoe seller, chemical worker, worker in the textile, leather and rubber industry or as a fur dyer cannot be learned.

Training to become a laboratory technician, masseur, salesperson in a leather goods store and in the paper, plastics and pulp industry is also likely to cause problems. But the acquired allergy is also noticeable in everyday life: Contact with newspapers, various textile dyes, dark-colored shoes, tool handles, bicycle and car tires can lead to new skin reactions that can worsen from case to case.

This is how you can protect yourself

The best protection is of course to avoid the henna tattoo. But if you don't want to go home without this holiday souvenir, you can get some clarity with a closer look and a few specific questions to the artist, who may not even know that his ink contains para-phenylenediamine. Of course, there is no such thing as black henna paste. If the artist offers black henna tattoos, the solution always contains additional color pigments, usually PPD.

If the artist evades the question about the ingredients or cannot answer them clearly, it is better not to let him touch your skin. If he answers the question about the exposure time with half an hour to two hours, this is just as much an indication of the addition of para-phenylenediamine as a guaranteed durability of the tattoo of one to two weeks.

In the case of products for home use, it is also advisable to take a look at the list of contents. Because they too can contain PPD. Very rarely, but in individual cases, the red dye Lawson contained in henna can cause skin irritation. A skin test, in which the henna ink is applied to a small area and this is then observed for two to three days, brings clarity.

mediscope - dzu