About 25% of Americans have at least one tattoo. For many, tattoos are a way to commemorate a special event in their lives or display an interest about which they are passionate. But some people who get tattoos, about 6% according to a recent study, can develop a severe, long-lasting reaction to the ink used during the tattooing process.

The reaction is akin to a rash and is characterized by severe itching and/or swelling that lasts for a few months or up to several years.

Dr. Marie Leger, a dermatologist at NYU Langone and the senior investigator of the study, says that some of these tattoo reactions can be treated with anti-inflammatory steroids, but notes that others required laser surgery to alleviate their symptoms. In extremely severe cases, excision surgery was necessary to remove the affected tissue.

It’s unclear why some people react negatively to tattoo ink. Leger notes that some of the reactions look like an immune response, but “to what?” is the lingering question. There’s a lack of standardization in the tattoo industry regarding the manufacture of tattoo ink, and until that changes, or more in-depth studies can be completed, getting a tattoo will be a game of roulette because there’s no way to tell who will have a reaction ahead of time.

So what can you do to protect yourself? Your homework. If you’re firm on the idea of getting a tattoo, investigate the shop you’re considering. Ask the owners and artists if anyone has ever had a bad reaction to a tattoo, or other complications, such as delayed healing or infection. Scope out their reputation with the Better Business Bureau and the Chamber of Commerce to see if there have been any complaints filed against the business.

And if you do get a tattoo you can’t live with, we’ve got the PicoSure laser at the ready to remove it.