A 4-year-old boy suffered severe burns after he had a henna tattoo placed on his arm.

Henna tattoos, which are derived from henna plant extracts, are designed to be temporary. They are thought to be medically safer than real tattoos since there are no needles involved.

However, some henna products are mixed with paraphenylenediamine, a cheap hair dye, which can cause burning.

Charlie Latimer began experiencing bleeding and blistering just a few days after having the design imprinted on his skin, the U.K.’s Daily Mail reported.

Doctors told Charlie’s parents the flower-shaped scar on his bicep could remain there for the rest of the boy’s life.

Charlie’s mother, Katie, 37, said she feels very guilty for allowing her son to get the tattoo.

“He will be scarred for the rest of his life,” she said. “My son’s beautiful, smooth 4-year-old skin is now all blistery and scarred.”

The incident took place when Charlie and his family were on vacation in Portugal.

Click here to read more from the Daily Mail and to see pictures of Charlie.