If your car has heated seats, you may have noticed an occasional rash on the back of your legs. That’s “toasted skin syndrome,” a new condition reported in the February 2012 issue of the Archives of Dermatology. The rash, known medically as erythema ab igne (EAI), indicates that you’ve been exposed to heat but haven’t been burned. This can happen if you frequently drive for an hour or so with the seat heat turned to the highest setting. The rash is worse on the leg that presses against the hot seat compared to the one extended to the gas pedal. The biggest concern here is cosmetic, but there’s also a chance that toasted skin syndrome could be mistaken for other dermatologic conditions or infections, leading to unnecessary tests. The same types of rash have been seen in people who use space heaters under their desks or use their laptops on their laps. The short-term treatment: turn off the seat heat, but be aware the rash can take months to disappear.