Topical oxygen therapy for diabetic foot ulcers: what the 2026 evidence shows

The foundation is still diabetic foot ulcer care

A diabetic foot ulcer is an open wound in a person with diabetes, often shaped by reduced sensation, repeated pressure and poor circulation. Infection can progress even when pain is mild or absent. A new ulcer deserves prompt assessment rather than a wait-and-see approach.

Good care starts with finding and treating the reasons the wound is not healing. Depending on the ulcer, a multidisciplinary plan may include:

• assessment for infection, loss of sensation, wound depth and reduced blood flow;
• pressure offloading chosen and fitted by the care team;
• professional debridement when appropriate, plus a dressing that manages fluid and protects a moist healing environment;
• antibiotics for a clinically diagnosed infection, and vascular assessment or revascularisation when blood supply is inadequate;
• support for glucose management, nutrition, kidney or heart disease, mobility and regular wound measurement.

The International Working Group on the Diabetic Foot, or IWGDF, states that local wound care cannot compensate for untreated infection, ischaemia or continuing trauma. Its 2023 guideline gives topical oxygen only a conditional, low-certainty recommendation as an adjunct when standard care alone has failed and suitable resources are available.

What topical oxygen means

Topical oxygen therapy is an umbrella term for approaches intended to increase oxygen at the wound surface. Delivery systems differ. Topical oxygen is also different from hyperbaric oxygen therapy, where a patient breathes oxygen inside a pressurised chamber. These treatments should not be treated as interchangeable.

What the 2026 systematic review found

In the pooled analysis, topical oxygen was associated with a higher chance of complete closure at 12 weeks, with a risk ratio of 1.53 and a 95% confidence interval from 1.14 to 2.05. Results were similar in one random-effects analysis. A more conservative sensitivity analysis produced wider uncertainty.

This is encouraging, but it is not a final answer. The estimate rests on three pooled trials and 325 participants. The authors called for larger, better reported studies, standardised outcomes, blinded outcome checks and direct comparisons of delivery approaches. The review also does not establish which patients benefit most, the best delivery method, long-term recurrence, amputation benefit, or cost effectiveness.

Category evidence is not product evidence

The distinction matters. A pooled result for topical oxygen as a treatment category cannot automatically be assigned to Granulox or any other named product. Different products can use different mechanisms, delivery systems and treatment schedules. A category review can support a conversation about the approach, but product-specific claims need product-specific comparative trials.

The Granulox publication linked below describes one 84-year-old man whose chronic diabetic foot ulcer improved after the spray was added to standard care. That is a case report. It has no randomised comparison and cannot separate the product's effect from concurrent care, changes in infection, pressure relief, circulation, or the natural course of the wound. It may help generate research questions, but it does not prove product efficacy.

Where topical oxygen may fit

A wound professional may discuss topical oxygen after checking that standard care is being delivered well and the ulcer is still not progressing. Selection should consider infection, circulation, wound depth and location, pressure exposure, exudate, treatment burden, cost and the person's ability to attend follow-up.

Even when a system can be used at home, this is not the same as self-directed care. Do not start a wound product, stop prescribed treatment, or use topical oxygen to postpone vascular, surgical or infection assessment. The team should define the goal, review progress and stop or change course if the wound deteriorates.

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