Question: how long does it take for a mole to fall off after liquid nitrogen?
Answer: The surrounding skin may swell and turn red. A blister forms over the growth and surrounding skin within 3 to 6 hours after we apply the liquid nitrogen. The blister might bleed a little and turn dark purple or black, which is normal. The blister flattens within 2 to 3 days and should fall off within 2 to 3 weeks.