Atmospheric Pressure Cold Plasma for Moderate-to-severe Tinea Pedis

The CAP group will additionally undergo atmospheric pressure cold plasma (CAP) treatment (plasma-activated gas form, CAP-Activated Gas; patent number: ZL202110209052.X, provided by Xi'an Jiaotong University), once daily for the first five days and every other day thereafter, for a total of 13 sessions. Each session will involve enclosing the target area in a treatment bag sealed with medical adhesive tape; plasma-activated gas rich in ozone (O₃) will be delivered and recirculated for 20 minutes, followed by plasma-activated gas rich in nitric oxide (NO) for an additional 5 minutes, in strict accordance with the standard operating procedures provided by the manufacturer.

In the placebo group, the electric field for plasma generation will remain off, so no plasma will be produced; only operational sounds will be simulated to maintain procedural blinding.

The group will receive standard care according to current clinical guidelines