New York: If you are considering getting yourself inked, just a word of caution. It may leave you prone to some chronic complications that may require surgical intervention, says a new study.

Researchers at New York University have found that as many as six percent of adult New Yorkers who get tattooed have experienced some form of tattoo-related rash, severe itching or swelling that lasted longer than four months and, in some cases, for many years.

"We were rather alarmed at the high rate of reported chronic complications tied to getting a tattoo," said senior study investigator and Marie Leger, a dermatologist.

The data showed that most long-lasting complications occurred in skin regions injected with the two most common tattoo ink colours, red and black.

"Given the growing popularity of tattoos, physicians, public health officials, and consumers need to be aware of the risks involved," she added.

Leger said some adverse skin reactions are treatable with anti-inflammatory steroid drugs, but others may require laser surgery.

For stronger reactions, surgery is sometimes necessary to remove tattooed areas of the skin or built-up scar tissue and granular skin lesions, which can rise several millimetres on the skin and cause considerable itching and emotional distress.

"It is not yet known if the reactions being observed are due to chemicals in the ink itself or to other chemicals, such as preservatives or brighteners, added to them or to the chemicals' breakdown over time," Leger said.

"The skin is a highly immune-sensitive organ, and the long-term consequences of repeatedly testing the body's immune system with injected dyes and coloured inks are poorly understood," the dermatologist said.

"Some of the reactions appear to be an immune response, yet we do not know who is most likely to have an immune reaction to a tattoo," she said.

The study appeared online in the journal Contact Dermatitis.

-IANS