Wound care items that are composed of calcium alginate. Calcium alginate is a component of seaweed. When in contact with a wound the calcium in the dressing is exchanged with sodium from the wound fluid. This turns the dressing into a gel that maintains a moist wound environment. Primarily used for exudating wounds as helps in debridement of sloughy wounds. Generally not used for low exudating wounds as this may cause dryness and scabbing.