I'm having problems with acne from lamictal lately too, also mainly on the jawline, neck, and lower half of my face. After googling it a bit back I read that it actually causes acne in those specific spots for a lot of people. I've been on it for about a year and a half, and this problem only started 3 or so months ago. I'm so pissed because about a month ago I tapered down to 200 mg and it mostly went away, but I felt the lamictal wasn't working then. So now I've upped it to 250 mg again, feel it working a bit, and the acne's back. I also used to get a recurrent but seemingly benign rash on my right forearm that I realized was from the lamictal, and it also went away at a lower dose so I'm waiting to see if it returns. I'm really hoping to get off the lamictal asap because of all this.

The good news is that at least it's probably just acne and not "the" rash. Also, since you're just now adjusting, maybe it'll be something that goes away for you? I should also mention that, aside from these problems, lamictal is great. Hope it works out for you! c: