Endoform is an FDA-cleared wound dressing made from the natural extracellular matrix (ECM) of sheep forestomach tissue. Unlike synthetic dressings that simply cover a wound, Endoform acts as a biological scaffold that helps your body rebuild damaged tissue from the ground up. It’s used on a wide range of wounds, from diabetic ulcers and pressure sores to surgical sites and burns.
How Endoform Is Made and What It Contains
Every cell in your body is surrounded by a mesh of structural proteins and signaling molecules called the extracellular matrix. This matrix gives tissues their shape, guides cell growth, and helps coordinate healing. Endoform is manufactured from ovine (sheep) forestomach tissue in a way that preserves this natural matrix intact, rather than breaking it down and reconstituting it the way many collagen-based dressings do.
Because the native structure stays intact, Endoform retains key biological components that play active roles in wound repair: collagen (the primary structural protein), elastin (which gives tissue flexibility), fibronectin (which helps cells attach and migrate), laminin (which supports the basement membrane beneath skin), and glycosaminoglycans (sugar molecules that help retain moisture and regulate growth factors). These aren’t added back in during manufacturing. They’re simply preserved from the original tissue.
How It Helps Wounds Heal
Chronic wounds often get stuck in a cycle of inflammation. One major reason is excessive protease activity. Proteases are enzymes that break down proteins, and at normal levels they’re essential for clearing damaged tissue. But when protease levels spike and stay elevated, they destroy new tissue as fast as the body can build it, preventing the wound from progressing.
Endoform works by absorbing and neutralizing those excess proteases. When protease levels in a wound are too high, the Endoform matrix gets digested instead of the body’s newly forming tissue. Clinicians can actually use this as a diagnostic signal: if the Endoform disappears quickly after application, it indicates protease levels are still elevated and more applications are needed. Once remnants of the dressing start persisting on the wound surface, it’s a sign that protease activity has dropped enough for the body’s own tissue-building cells (fibroblasts) to lay down a new extracellular matrix that won’t be immediately destroyed.
At the same time, the intact ECM structure serves as a physical scaffold. Cells can migrate into and across it, using it as a template to build granulation tissue, the pink, healthy tissue that fills in a wound bed before skin closes over it.
Types of Wounds It Treats
Endoform is FDA-cleared for a broad list of wound types:
- Chronic wounds: pressure ulcers, venous ulcers, diabetic ulcers, and other chronic vascular ulcers
- Surgical wounds: donor sites, skin graft sites, wounds after Mohs surgery or laser surgery, podiatric wounds, and wound dehiscence (surgical sites that reopen)
- Trauma wounds: abrasions, lacerations, second-degree burns, and skin tears
- Tunneled or undermined wounds
- Draining wounds
It can be used on both partial-thickness wounds (where only the top layers of skin are damaged) and full-thickness wounds (where damage extends through all skin layers into deeper tissue).
Endoform Natural vs. Endoform Antimicrobial
Endoform comes in two versions. The standard product, Endoform Natural, is 100% extracellular matrix with no added agents. The antimicrobial version adds a small amount of ionic silver (roughly 0.3% by weight) to the same ECM scaffold. This silver is designed to prevent bacteria and fungi from colonizing the dressing itself, with antimicrobial effectiveness lasting up to seven days per application.
The antimicrobial version is effective against a wide range of organisms, including MRSA, vancomycin-resistant enterococci (VRE), Pseudomonas, E. coli, and several species of Candida fungus. It can be applied directly over infected tissue, which sets it apart from many other biological dressings that require a clean wound bed first. Both versions can be used under compression therapy, a common treatment for venous leg ulcers.
How Endoform Is Applied
The application process is straightforward. The wound is first cleaned with sterile saline or an approved wound cleanser. The surrounding skin is dried, and the Endoform sheet is trimmed to fit the wound while still making contact with the wound edges. It’s placed dry onto the wound bed, then moistened with saline so it conforms to the underlying tissue. Moisture is essential for the dressing to function. For very dry wounds, a thin layer of hydrogel is applied on top of the Endoform to maintain hydration.
A non-adherent contact layer goes over the Endoform, followed by a secondary dressing to manage moisture and absorb drainage. The dressing stays in place for three to seven days. At the next dressing change, any Endoform that hasn’t adhered well is gently removed, the wound is irrigated and debrided if needed, and a fresh piece is reapplied. If residual Endoform appears brown and crusty but is firmly attached, it’s left in place and simply rehydrated with hydrogel. This residual material is a sign of integration, not a problem.
Clinical Results
In a published case series of nine patients with chronic soft tissue defects treated with ECM graft-augmented flap closure using Endoform, seven of the nine wounds healed without complications. The two remaining cases developed dehiscence (the wound partially reopened), but both went on to heal on their own without additional surgery. One of those healed by eight weeks after the initial procedure, the other by three months. These were complex, long-standing wounds that had resisted other treatments, so the overall success rate was notable.
Endoform is typically used as part of a broader wound care plan. The dressing handles the biological environment inside the wound, but factors like compression therapy for venous ulcers, offloading pressure for diabetic foot wounds, and adequate nutrition all play roles in the final outcome.
Who Should Not Use Endoform
Because Endoform is derived from animal tissue, anyone with a known sensitivity to its components should avoid it. While it comes from sheep rather than cattle, the broader category of animal-derived wound dressings has been associated with occasional allergic reactions, including redness, rash, itching, hives, and localized skin blanching. These reactions are uncommon but worth being aware of, especially if you have a history of sensitivity to animal-derived collagen products. FDA labeling requirements mandate that any known material sensitivities or incompatibilities with other therapies be clearly listed on the product packaging.