Why do scabs form?

Scabs are the hard crusts that grow over wounds on the skin as they heal. Scab development is a typical component of the wound healing process. When an injury occurs, the early steps of wound healing try to limit blood loss by forming blood clots. Many different types of molecules in the blood combine to generate these blood clots. Clots arise as a result of blood vessel leaking.

After the clots have sealed the blood arteries, the processes of tissue and skin regeneration begin. The blood clot over the site of damage transforms into a hard scab when the skin re-grows over the wound. Scab development is easily seen in small injuries caused by cuts and falls during daily activity. Tissue healing and scab development occur quickly in these mild lesions.

The scab is pushed out when fresh skin and tissue regenerate over the wound site. Eventually, the scab becomes loose enough to be plucked off or falls off on its own. Picking off a scab prematurely, on the other hand, might cause more bleeding if the underlying lesion hasn't healed entirely. This would cause a delay in wound healing and the creation of a new scab.