CYP2C19*2 (681G>A, rs4244285) and CYP2C19*3 (636G>A, rs4986893) variants were associated with predisposition to Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) after CBZ administration and the absence of CYP3A5*3 (rs776746) might be a protective factor [69,70]. Here, CYP2C19 is linked to toxic epidermal necrolysis.