Acids remove outer skin layers so it heals smoother, brighter, and more even. Best evidence: lightening brown patches and sun spots and improving texture and tone, about as well as laser at far lower cost; deeper peels soften wrinkles. Main downside is new discoloration, especially in darker skin, so gentler peels are chosen there. (Full Review)

Protocol

Superficial Series

Glycolic acid 20–70% or salicylic acid 20–30%

4–6 sessions, 2–4 weeks apart; maintenance every 1–3 months. Most skin tones.

Medium-Depth Peel

Trichloroacetic acid 35%, over glycolic acid 70% or Jessner's solution

Single treatment to a visible frost endpoint, repeated every several months as needed.

Deep Peel

Phenol-croton oil formula

One-time, staged full-face procedure under monitoring. Lighter skin, significant wrinkling.

Time to effect

Texture & Brightness

Within days; 1–3 sessions

Visible brightening and smoother texture appear within days of the first treatment.

Pigment Reduction

Over a 4–6 session series

Cumulative pigment and texture gains accrue across the series.

Collagen Firmness

Weeks to months

Firmness from deeper peels develops gradually over weeks to months.

Benefits

High: Improvement of melasma and hyperpigmentation; improvement of skin texture, brightness, and fine surface lines

Medium: Reduction of acne and post-acne marks; improvement of moderate photoaging and wrinkles; treatment of precancerous sun damage

Low: New collagen formation and modest firmness

Speculative: Long-term skin "field" rejuvenation and cancer risk reduction

Contraindications

Active skin infection or open lesions in the treatment area (absolute, until resolved)

Pregnancy or breastfeeding (medium/deep and certain agents)

Uncontrolled inflammatory skin disease (active eczema or psoriasis in the area)

Very recent isotretinoin (within ~6–12 months) for deep resurfacing

Unrealistic expectations about superficial peels correcting deep wrinkles or laxity

Key Interactions

Oral isotretinoin (Accutane)

Topical retinoids (tretinoin, adapalene) and exfoliating acids

Photosensitizing drugs and supplements (doxycycline, retinoids, St. John's Wort)

Hydroquinone and other lightening agents

Anticoagulants and procedures with bleeding risk

Other resurfacing procedures (laser, microneedling, dermabrasion)

Risk & Side Effects

High: Post-inflammatory hyperpigmentation and dyspigmentation; transient redness, stinging, peeling, and crusting

Medium: Infection and delayed healing; scarring

Low: Phenol-related cardiac and systemic toxicity; persistent redness, texture lines of demarcation, and milia

Speculative: Long-term barrier or sensitization effects from frequent home peeling

Monitoring

Marker	Target	Why
ECG / heart rhythm	Normal sinus rhythm, no arrhythmia	Phenol can trigger heart rhythm disturbances during deep peels
Liver enzymes (ALT, AST)	ALT/AST roughly 10–26 U/L	Phenol is metabolized by the liver; screens for impaired clearance
Kidney function (creatinine, eGFR)	eGFR >90 mL/min/1.73m²; creatinine low-normal	Phenol is excreted renally; impaired function raises toxicity risk
Skin tone (Fitzpatrick type)	Type matched to chosen peel depth	Determines pigment-complication risk and guides agent/depth

Cadence: Every 2–4 weeks during a series, then every 1–3 months; continuous cardiac monitoring during deep phenol peels.

Qualitative Assessment

Visible brightening and more even skin tone
Smoother texture and refined-looking pores
Reduction in the size or darkness of brown patches and sun spots
Softening of fine surface lines
Subjective satisfaction and confidence in skin appearance
Absence of new dark marks, prolonged redness, or scarring

Chemical Peel for Skin Rejuvenation

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment