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This page describes products and general use; it is not medical advice.
A hydrocolloid dressing is a self-adhesive wound dressing built around a gel-forming layer. Clinic staff, buyers and students use this page as a product reference: what the dressing is made of, how it behaves, the variants and sizes that exist, and the cautions that published professional guidance attaches to it. It is used mainly by nurses and wound-care clinicians, and the people who stock supplies for them.
What a hydrocolloid dressing is
Hydrocolloids are occlusive dressings that contain a gel-forming agent, such as carboxymethylcellulose, pectin or gelatine, combined with adhesives and applied to a polyurethane foam or film to create a single-layer adhesive dressing (Hedger, Wounds UK). Its purpose is to keep a wound covered and moist while it absorbs light to moderate fluid. It sits within the broader group covered in what a wound dressing is, alongside gauze and the bandage family.
Hydrocolloids were introduced in the 1980s and were originally developed as stoma products, used as a barrier over excoriated skin (Hedger, Wounds UK).
How it works and how it is built
The gel-forming particles sit in an adhesive matrix that is bonded to a backing layer. The same construction is described by a manufacturer, Avery Dennison Medical: carboxymethylcellulose and pectin in an adhesive matrix on polyurethane film, nonwoven or thin foam.
- Gel formation. When fluid from the wound (exudate) is present, the dressing forms a hydrophilic gel.
- Moist, occlusive cover. The dressing is occlusive, yet it becomes progressively more permeable as gelling takes place, so some water vapour is lost and absorbency increases.
- Debridement support. The moist environment aids autolytic debridement, softening and rehydrating dead tissue and slough.
- Regulatory frame (US). The FDA regulation for occlusive wound dressings, 21 CFR 878.4020, describes a nonresorbable device intended to cover a wound, provide or support a moist wound environment and allow exchange of gases such as oxygen and water vapor. It is a Class I device and is exempt from 510(k) premarket notification, subject to the limitations in 21 CFR 878.9. The classification excludes dressings with added drugs such as antimicrobials, added biologics such as growth factors, or materials derived from animal sources.
Types and variants
| Variant | Typical use | Key difference |
|---|---|---|
| Bordered or unbordered | Adhesion to surrounding skin | Choice affects how the dressing is held in place (Hedger) |
| Triangular shape | Sacral area | Normally designed for the sacral area (Hedger) |
| Change-indicator line | Timing of dressing changes | Some products have a line showing when to change (Hedger) |
| Thick or thin, bevelled edges | Absorbency and adherence | Thickness and edge design are chosen for absorbency and adherence (Hedger) |
| Thin-film hydrocolloids | Products listed in a primary care formulary | The NHS Lothian formulary lists hydrocolloids to facilitate debridement and rehydration in minimally exuding wounds |
| Gelatine-containing | Product composition | Not all hydrocolloids contain gelatine; where present it is often pork-derived, which can matter to vegetarian, vegan or cultural preferences (Hedger) |
Sizes listed in a published formulary
Size ranges differ by manufacturer. The NHS Lothian Joint Adult Formulary (primary care wound management products) lists these hydrocolloid sizes:
| Product (as listed) | Sizes |
|---|---|
| Hydrocoll Thin Film | 7.5 cm x 7.5 cm, 10 cm x 10 cm, 15 cm x 15 cm |
| Tegaderm Hydrocolloid Thin | 10 cm x 12 cm, 13 cm x 15 cm |
How to choose: criteria that guidance states
| Consideration | What the source says |
|---|---|
| Exudate level | Designed for light to moderately heavy exudate (Hedger); the formulary lists minimally exuding wounds; a manufacturer describes low to moderate exudate. If the dressing cannot control the exudate, the skin around the wound can become macerated (Hedger). |
| Skin around the wound | Needs healthy surrounding tissue to adhere to (Hedger). |
| Change frequency | Left in place a minimum of 3 days and a maximum of 7; not the dressing of choice where daily changes are needed (Hedger). |
| Infection | Not suitable for clinically infected wounds (NHS Lothian formulary); should not be used on full-thickness burns or infected wounds (Hedger). |
| Foot and heel wounds | Caution on black necrotic heels and diabetic feet, where reduced arterial supply and occlusion may encourage anaerobic bacteria; daily changes are advised for diabetic foot wounds, so it is not the best choice there (Hedger). |
| Over-granulation | Can occur; the review suggests moving to a more permeable type such as a foam or film (Hedger). |
Hedger notes that wounds where hydrocolloids are used include sloughy wounds, dry black eschar needing hydration, surgical wounds, abrasions and minor burns, and that occlusion can reduce pain in partial-thickness wounds. The review also states that dressings do not heal wounds: pressure ulcers need pressure relief and venous leg ulcers need compression.
Safe use and handling basics
These points come from the Wounds UK review and a manufacturer page, and describe general product use, not instructions for an individual patient. Follow the manufacturer’s instructions for the specific product and the directions of the treating clinician.
- Size the dressing so it overlaps normal skin: the Wounds UK review gives 3 cm, while Avery Dennison Medical states at least 1 inch (about 2.5 cm) beyond the wound edges.
- Warming the dressing between the hands helps adherence (Hedger).
- No secondary dressing is needed, and the dressing is waterproof, so showering is possible (Hedger).
- Peel the dressing off slowly (Avery Dennison Medical).
- The dressing can be cut to shape, but the manufacturer’s directions must be followed (Hedger).
- A noticeable odour on removal does not by itself mean a wound problem, and the wound can look larger at first because of debridement (Hedger).
- Change the dressing when exudate is about 1-2 cm from the dressing edge, or at 7 days (Hedger).
Common mistakes
- Using a hydrocolloid where daily changes are needed, such as diabetic foot wounds.
- Using it on a clinically infected wound.
- Applying it to a wound that produces more exudate than it can hold, which risks maceration of surrounding skin.
- Expecting the dressing alone to heal a pressure ulcer or venous leg ulcer.
- Assuming every hydrocolloid is gelatine-free or vegetarian-suitable.
Frequently asked questions
What is a hydrocolloid dressing used for?
It covers wounds that produce light to moderate fluid, and it supports a moist environment and debridement of dead tissue. Published uses include sloughy wounds, surgical wounds, abrasions and minor burns.
Is a hydrocolloid dressing waterproof?
The Wounds UK review states it is waterproof and that showering is possible.
How long does a hydrocolloid dressing stay on?
The review gives a minimum of 3 days and a maximum of 7, with an earlier change when exudate reaches about 1-2 cm from the edge.
Is a hydrocolloid dressing a regulated device?
In the US, occlusive wound dressings are Class I devices under 21 CFR 878.4020 and exempt from 510(k), subject to the limitations in 21 CFR 878.9.
Where can I read about related dressing supplies?
See the wound care supply selection guide, the wound care clinic supply checklist and what medical tape is. Retail categories for wound dressings are listed at wound dressings.
Sources
- Hedger C. “Choosing the appropriate dressing: hydrocolloids.” Wounds Essentials, 2012, vol 2, pp 13-14. Wounds UK. https://wounds-uk.com/wp-content/uploads/2023/02/content_10715.pdf (checked 2026-10-28)
- NHS Lothian Joint Adult Formulary, chapter 19, Primary Care Wound Management Products, hydrocolloid section. https://www.rightdecisions.scot.nhs.uk/nhsl-medicines-guidance/joint-adult-formulary/chapter-19-wound-management/primary-care-wound-management-products (checked 2026-10-28)
- 21 CFR 878.4020, Occlusive wound dressing, US Code of Federal Regulations. https://www.law.cornell.edu/cfr/text/21/878.4020 (checked 2026-10-28)
- Avery Dennison Medical, how hydrocolloid patches work, manufacturer page. https://medical.averydennison.com/en/home/markets/wound-care-skin-care/understanding-how-hydrocolloid-patches-work.html (checked 2026-10-28)
