Can a Dr test a hidden part of my skin with a laser before a resurfacing procedure to see if it would cause hypopigmentation?

Currently the most common type of laser for resurfacing the skin is the fractional co2 laser. It is very safe and complications of hyper/hypo pigmentation are rare. If you have a darker skin color your risk is relatively higher than a whiter skin color. I have in the past test spotted the laser on certain patients that are darker such as middle eastern. Also I have made a decision not to laser someone based on the test patch. You do have to wait at least 6 weeks to tell if there would be prolonged huperpigmentation. please consult with a physician experienced in laser skin resurfacing. 

Hello, and thank you for this questions. Yes we can go ahead and spot treat an area to see if the patient would develop hypopigmentation. This is very uncommon with the newer fractional lasers. I would recommend she seek out a qualified board certified plastic surgeon and/or dermatologist in your area has experience and expertise in laser treatments. Best of luck.