I'm on a biolgic treatment for rheumatoid arthritis (Orencia) can I get a tatoo?

This is a good question for your doctor.
I don’t remember reading any restrictions about tattoos when I was on Remicade (another biologic) but I’m not a doctor.

I don’t know if this a rule for all tatoos, but I remember meeting a woman who had cosmetic tatoos done. She said she had to get medication for herpes because if you broke out while you were healing from the tatoo, it could cause permanent scarring (called kelloids).