A warning has been issued about a specific type of henna tattoo

Don't learn the hard way.

We've probably all had a henna tattoo at some stage in our lives. Whether it was on holiday or at festival, we just can't resist the body art. While the majority are harmless and wash off after a few days, a warning has been issued about a specific type of henna tattoo. The NHS, in the UK, is advising people to avoid black hennas. An increasing amount of cases are arising of people having allergic reactions after getting a black henna. Black hennas, as opposed to the red or brown variety, can cause serious burns to the skin. It contains high volumes of Paraphenylenediamine (PPD) which has a dangerous reaction when it comes in contact with the skin.

I know the feeling lad pic.twitter.com/C19kKeU7n8

— Møż (@Harry___Morris) July 11, 2017

According to The Mirror, the NHS has said:

"If you see a shop or stall offering to paint black tattoos onto your skin, don’t be tempted to get one. It could leave you scarred for life and put you at risk of a life-threatening allergic reaction. Often called "black henna" or "neutral henna" tattoos, these patterns painted onto your skin are readily available abroad. They may also be available in the UK, at festivals and fairs, and to buy online. But the black paste used in these temporary tattoos may contain high levels of a chemical dye so powerful and toxic that it is illegal to use it on the skin in this way."

As a rule of thumb, only get a henna tattoo if it has a red, brown or orange based colour.