How does TCA CROSS work?

The clinician applies trichloroacetic acid to the base of an individual ice-pick or narrow depressed scar rather than spreading it across the whole face. The acid creates a focused injury. During repair, the area can produce collagen and remodel the scar edges, so the pit may look shallower over a course of treatments. It is designed for selected depressed acne scars, not every type of scar or active acne. Redness, a small crust, darkening, or temporary irritation can occur while the treated points heal.

Attend an assessment so the scar type, skin tone, and history of dark marks can be considered. Follow the clinic's cleansing and sun-protection instructions. Do not pick crusts, rub the treated points, or apply unapproved acids and retinoids while the skin is recovering. Tell the clinician about recent tanning, cold sores, pregnancy, medicines, and a tendency to form raised scars. Results depend on scar structure and healing, and improvement is gradual rather than immediate.

Contact the treating clinician if pain, swelling, warmth, drainage, or redness is increasing instead of settling, or if the area develops spreading redness or fever. Seek urgent medical help for facial swelling affecting breathing or vision. New persistent darkening, pale patches, or a raised scar also merits review so treatment can be adjusted.

Which scar types are being treated, and what healing changes should I expect? How will my risk of post-inflammatory colour change be managed? What products should I pause, and when may I restart them?