Footlight San is a powdered topical medication commonly used to treat tinea capitis and sweaty hands and feet, and is clinically effective in that its main effects are to dry dampness, kill insects, and relieve itching, and its main ingredients include salicylic acid, bitter ginseng, and talcum powder. Certain patients with tinea pedis often choose to treat tinea pedis by dissolving the foot light powder in water because salicylic acid has the effect of dissolving keratin, so for certain hyperkeratotic tinea pedis, the foot light powder is more suitable, while for impregnated vesicular tinea pedis and blistering tinea pedis, it is recommended that other antifungal drugs can be used topically. If the concentration is too high when used, it can lead to local keratolytic relaxation especially, and in serious cases, it can induce contact dermatitis and irritant dermatitis, with clinical manifestations of local edematous erythema accompanied by pruritus, so the concentration ratio is especially important when using Footlight San.