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This page describes products and general use; it is not medical advice.
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An antimicrobial wound dressing is a wound dressing that either carries an antimicrobial agent or physically binds microbes so that fewer remain in the wound. Clinic staff, buyers and students use the term for silver, iodine and DACC-coated products. This guide explains the one split that matters when comparing them, and how the FDA documents describe these devices.
What an antimicrobial wound dressing is
The category covers dressings sold as antibacterial, antiseptic, silver-impregnated (often written “Ag”), iodine-based or microbe-binding. FDA clearance records for two examples place them under product code FRO, regulatory class “Unclassified”; the silver example’s record gives the classification name “Dressing, Wound, Drug”. Who uses the term: clinic staff who select dressings, buyers who stock them, and students learning product classes.
How they work: agent-releasing versus physically acting
The FDA 510(k) summary for Sorbact Wound Dressing states the contrast directly: Sorbact “acts by adsorption to remove bacteria from a wound, while Colactive AG and Triosyn T40 include an antimicrobial active substance as part of the device.” That is the split to hold on to.
Agent-releasing: silver (Ag) dressings
In the cleared KerraContact Ag Perf dressing, oxidized silver species are deposited on a non-woven spunlace polyester layer laminated between Delnet HDPE mesh layers. The FDA summary gives a silver concentration of 0.4 mg/cm² (4.5% w/w), states that the dressing inhibits bacterial growth in the dressing for up to 7 days, and reports in vitro effectiveness against S. aureus, E. coli, E. faecalis, S. epidermidis, P. aeruginosa and A. baumannii. It is sterilized by gamma irradiation. For silver alone, see silver wound dressings.
Agent-releasing: iodine dressings
Iodine dressings carry an iodine-based agent, most often povidone-iodine or cadexomer-iodine. Types, listed sizes and handling points are covered in our iodine dressing guide.
Physically acting: DACC-coated dressings
Sorbact dressings are coated with DACC, which the FDA summary spells “dialkyl carbamoyl chloride” and describes as a hydrophobic (water-repelling) fatty ester acid that binds hydrophobic microorganisms and reduces their overall concentration in a wound each time the dressing is changed. The summary lists adsorbent dressings, compresses, ribbon gauze tamponades, round swabs and surgical dressings, made on hydrophobic acetate or cotton fabric, with a non-woven viscose core in the absorbent pad.
Types and variants
| Type | How it acts | Key difference | Source |
|---|---|---|---|
| Silver (Ag) dressing, e.g. KerraContact Ag Perf | Carries oxidized silver; inhibits growth in the dressing for up to 7 days | Antimicrobial agent is part of the device (0.4 mg/cm²) | FDA 510(k) K182680 |
| DACC-coated dressing, e.g. Sorbact | Hydrophobic coating binds hydrophobic microbes, removed at dressing change | Acts by adsorption, with no antimicrobial agent released | FDA 510(k) K063059 |
| Iodine dressing (povidone-iodine, cadexomer-iodine) | Iodine-based agent | Agent-releasing; see the iodine guide for types and sizes | CASRAI iodine dressing guide |
How FDA classifies them
Both cleared examples above are listed as class “Unclassified” with product code FRO. The silver dressing’s record gives the classification name “Dressing, Wound, Drug”; the Sorbact summary gives panel General and Plastic Surgery and states that no performance standard is applicable. The FDA letter for the silver dressing adds that “some cleared products may instead be combination products” and points to the 510(k) Premarket Notification Database, which identifies combination product submissions. To check a specific product, search that database by its K-number.
Reading the label: prescription and over-the-counter
Each K-number covers its own product and its own indications. The FDA summary for Sorbact lists a prescription indication and a separate, narrower over-the-counter indication for the same dressing family, so the label of the exact product is the document to read. Product selection for a patient is a clinician decision.
Storage and handling basics
Follow the manufacturer’s instructions for use for the exact product, and check that the package is sterile and intact. For general dressing basics see what is a wound dressing; for antiseptic liquids see antiseptics for wound care.
Common mistakes
- Treating “antimicrobial” as one mechanism. Silver and iodine dressings include an active substance; DACC dressings act by adsorption.
- Assuming every brand is described by the same clearance. Each K-number covers its own product and indications.
- Reading an over-the-counter indication as the prescription indication, or the reverse; check the label of the exact product.
FAQ
What is wet to dry wound dressing?
Wet to dry is not a product named in the FDA documents cited on this page, so this guide does not describe it. For dressing types in general, start with what is a wound dressing.
What is Adaptic wound dressing?
Adaptic is a non-adhering dressing, covered on its own page: what is Adaptic. See also non-adherent dressings.
Is an antibacterial or silver dressing the same as an antiseptic dressing?
Not necessarily. Silver and iodine dressings carry an agent; a DACC dressing binds microbes without one. Which term a label uses depends on the product.
Sources
Checked 1 November 2026.
- FDA 510(k) K182680, KerraContact Ag Perf Advanced Perforated Silver Wound Dressing, Exciton Technologies; FDA letter dated 6 December 2018: https://www.accessdata.fda.gov/cdrh_docs/pdf18/K182680.pdf
- FDA 510(k) summary K063059, Sorbact Wound Dressing, Abigo Medical AB: https://www.accessdata.fda.gov/cdrh_docs/pdf6/K063059.pdf
- CASRAI, iodine dressing guide: /guides/iodine-dressing
