Hi, I used a heavy foundation "cover up" creme over the worst of it (derma blend or similar), when having to grow it out prior to treatment, then I would park just before the appointment, and use a make up wipe to clean it off and apply the emla creme (lidocane).
I agree it's very triggering for GD. I endured treatments for like 6 years (300 + hours in the chair).
Hugs and hang in there dear....
C -