There are several methods that can be used to remove a
skin tag.The three ways doctors remove
skin tags is by cutting them off, burning them, or freezing them. Skin tags can be cut off with a scalpel or medical shears. They can be burned off with a medical cautery device or they can be frozen with liquid nitrogen, in which case the skin tag then falls off. In all three instances, the idea is to stop the blood flow to the skin tag."
ref:http://www.easyskintagremoval.com/remove-skin-tags.