Electrocautery is a way to remove a wart/spot/Freckle using heat from electricity. The electricity is used to heat the needle which is put on the spot. The electricity is not sent into your body. Electrocautery usually leaves behind a wound which may take 1 to 3 weeks to heal. The time it takes the wound to heal depends on the size of the spot/wart/freckle. Bigger warts, freckle take longer to heal. But the wart may need to be treated more than.