Reactions in tattoos generally fall into one of four groups. The reactions in one group consist in the immediate response of the skin to the physical injury of tattooing. This is rarely accompanied with or followed by secondary infection. In rare instances keloid,1 melanoma,2 severe pyogenic infection,3 amputation,3 gangrene3 and even death3 have been reported as direct consequences of tattooing.
Allergic reactions to the material used in tattooing can occur immediately or at any time during the existence of the tattoo. Allergic reactions to mercury, usually used in the red part of tattoos, have been most frequently noted.4 The allergic dermatitis may either be confined to the tattoo or be generalized. The allergenic mercurial compound causing the dermatitis need not be the mercuric sulfide (cinnabar) in the tattoo, but it can be any form of mercury which is used on the skin