An alginate dressing is a wound dressing made from alginate, a natural substance found in brown seaweed. It may contain calcium alginate, sodium alginate, or both. When the dressing absorbs fluid from a wound, it turns into a soft gel.

This change happens through ion exchange. Calcium in the dressing trades places with sodium in the wound fluid, which makes the fibers swell and form the gel. The gel keeps the wound moist and sits close to the wound surface while the dressing continues to absorb fluid. Calcium alginate dressings may also help control minor bleeding.

Alginate dressings are used on wounds that produce moderate to heavy fluid. Depending on the product, they may be used on venous leg ulcers, diabetic foot ulcers, pressure ulcers, some surgical or traumatic wounds, superficial burns, and skin-graft donor sites. Some products also contain silver, collagen, honey, or hyaluronic acid.

The dressing is soft, flexible, and absorbent. Once wet, the gel adapts to uneven wound surfaces and makes the dressing less likely to stick during removal. If the dressing dries out, it may stick to the wound and become harder to remove.

Alginate dressings need wound fluid to form a gel, so they are usually not suitable for dry wounds or wounds that produce very little fluid. They are also not normally used on wounds covered with hard, dry, dead tissue (eschar). Results vary with the ingredients, the amount of wound fluid, and the specific product.

Disclaimer: This information is for general educational purposes only and does not replace professional medical advice, diagnosis, or treatment. Consult a qualified healthcare professional for advice about any health concern.