Which of the following indicates a contra-action during high-frequency treatment?

• A. Excessive erythema indicating over-stimulation of the skin.
• B. Slight tingling in the treated area.
• C. Mild warmth that fades quickly.
• D. Normal skin coloration after treatment.

Answer: (A)

Contra-actions during high-frequency treatment indicate the skin is being over-stimulated. Excessive erythema means the current is too strong or applied for too long, causing exaggerated redness from excessive vasodilation and irritation. This is a warning sign that you need to reduce the intensity, shorten the duration, or pause the treatment to protect the skin. In contrast, slight tingling and a mild warmth that fades quickly, along with normal skin coloration after treatment, are typical, tolerable responses that show the skin is reacting to the treatment without being overstimulated.