While any rash should be checked out, Dr. Phelps of psycheducation.org gives more specific information about rashes and lamictal and dangerous rashes and lamictal. Details on the Lamotrigine Rash | PsychEducation

The part where it is on the face and near/on mucus membranes is where mine got scary; I had it my lips and an eyelid and had itching in my mouth. Needless to say I was pulled off immediately and can't ever try it again. Often rashes can be cleared and you can try again with a slower taper if indicated.

It took about 1 second to diagnose when I saw the doctor.

Funny thing was I was positive it wouldn't happen because I'd been on lamictal before without the rash and while I tend to have bad reactions to meds I was sure I'd get nothing more than a few headaches and some nausea like the last time. Surprise!

I wish I had pictures.