A hydrocolloid is a moist wound healing dressing. It is an active gel containing particles that absorb excess wound liquid. The dressing swells to form what appears to be a white bubble, creating a shock-absorbent layer which protects the wound from further rubbing. The hydrocolloid in Compeed Blister Cushions acts as a second skin to maintain the natural moisture levels, allowing fast wound healing with no scab and therefore reducing the risk of scarring.