Is it safe to kiss someone with stevens-johnson syndrome?

Yes, unless . . .: Stevens johnson syndrome is a severe, sometimes fatal, allergic reaction. It is not contagious. About half of the cases have no identifiable cause. Of the cases with a known cause, more than half of them are due to medications. Some cases are due to herpes simplex, mycoplasma, or other infectious germs. It should be safe to kiss an sjs patient unless either person has a cold sore on the lips.

Yes: It is not contagious but sjs tends to affect the lips and mucus membranes so it might be painful to the patient with sjs.