Chemical Peels Adelaide: Evidence-Based Professional Treatment Guide

Glycolic Acid (20-60%)

Molecular Weight: 76 Daltons – smallest AHA molecule = deepest AHA penetration

Clinical Evidence: Studies demonstrate 31% increase in collagen density, significant improvement in photodamage and fine lines. Murad’s Replenishing Multi-Acid Peel accelerates cell renewal by 33% in seven days.

Best For: Aging concerns, uneven texture, dull complexion, photoaging

Available: Multiple Murad professional formulations including multi-acid combinations

Salicylic Acid (20-30%)

Type: Beta hydroxy acid (BHA) – lipophilic (oil-soluble)

The Acne “Lightbulb Moment”: Unlike water-soluble AHAs that work on the skin surface, salicylic acid is oil-soluble. This means it can penetrate INTO sebaceous follicles (pores) where acne actually forms. Think of it like this: your pores are filled with sebum (oil). Water-based acids can’t penetrate oil, but oil-soluble salicylic acid dissolves right into it, traveling deep into the pore to:

• Dissolve the keratin plugs (comedones/blackheads)
• Clear out dead skin cells and debris trapped in sebum
• Reduce inflammation inside the follicle
• Normalize the keratinization process that creates blockages

Clinical Evidence: Gold standard for acne treatment – 40-70% reduction in inflammatory lesions. This is why salicylic acid works for acne when other exfoliants don’t – it gets to the source.

Best For: Oily skin, active acne, blackheads, congestion, enlarged pores

Available: Murad Daily Clarifying Peel

⚠️ Contraindication: Aspirin allergy (salicylic acid is related to aspirin), pregnancy

Lactic Acid (30-50%)

Molecular Weight: 90 Daltons – larger than glycolic = gentler penetration

Unique Property: Humectant properties provide hydration while exfoliating

Clinical Evidence: Comparable efficacy to glycolic with better tolerability

Best For: Sensitive or dry skin, aging, hyperpigmentation

Available: Featured in Murad multi-acid formulations

Mandelic Acid (30-50%)

Molecular Weight: 152 Daltons – largest AHA = slowest, gentlest penetration

Unique Properties: Antibacterial and anti-inflammatory

Clinical Evidence: Effective for acne, suitable for darker skin tones (Fitzpatrick IV-VI) with lower PIH risk

Best For: Acne-prone skin, sensitive skin, higher Fitzpatrick types, rosacea

Trichloroacetic Acid (TCA 20-35%)

Mechanism: Causes protein coagulation and keratolysis

Clinical Evidence: Extensively studied for moderate photodamage, wrinkles, acne scarring

Concentration Determines Depth:

• 20-30% TCA: Superficial to medium depth
• 30-35% TCA: True medium-depth penetration

The Frosting Response – Visual Indicator of Penetration:

“True Frost” (TCA): White frosting indicates protein denaturation – the actual coagulation of skin proteins. This is a reliable indicator of treatment depth:

• Light frost: Superficial effect (patchy white)
• White frost: Medium-depth achieved (uniform white coating)

“Pseudo-Frost” (Salicylic Acid): White precipitate that looks like frost but is actually the acid recrystallizing on skin surface – NOT protein denaturation. This is a common source of confusion during salicylic treatments. The white appearance doesn’t indicate penetration depth like TCA frost does.

Research Note: Studies show combining 70% glycolic acid followed by 15% TCA increases skin elasticity and hydration while reducing melanin index more effectively than TCA alone.

Acne Treatment

Research Findings: Comparative studies show both glycolic acid and salicylic acid effectively treat acne, with salicylic demonstrating faster response. Study comparing 45% mandelic with 30% salicylic found both equally efficacious, with mandelic better tolerated.

Mechanism: Lipophilic acids penetrate sebaceous follicles, dissolve comedone contents, reduce inflammatory cytokines, normalize follicular keratinization.

Protocol: 4-6 treatments every 2-4 weeks using salicylic or mandelic acid, then maintenance as needed.

Photoaging & Wrinkles

Research Findings: Studies on 50% glycolic peels show improvement in mild photoaging, including decreased rough texture, fine wrinkling and solar keratoses. Histological analysis reveals increased collagen thickness in dermis and epidermal thickening.

The Collagen Cascade (How 31% Increase Happens): When AHAs create controlled injury to the epidermis, this triggers release of specific cytokines – particularly TGF-beta (Transforming Growth Factor-beta). These chemical messengers travel from the epidermis down to the dermis, where they signal fibroblasts to produce new Type I collagen. This is why you see collagen improvement from a treatment that technically only penetrates the epidermis – it’s the inflammatory signaling cascade that reaches deeper.

Medium-Depth Evidence: TCA 20-35% or combination GA/TCA demonstrate statistically significant improvement in skin elasticity (measured objectively), hydration levels, reduction in melanin index, decreased erythema, and visible wrinkle reduction.

⚠️ Limitations: Glycolic peels do not affect deep wrinkles or deep dermal pigmentation – realistic expectations essential.

Melasma & Hyperpigmentation

Research Findings: Comparative studies show 15% TCA and 35% glycolic acid equally effective for melasma – 70% of glycolic patients and 64% of TCA patients reported good to very good response.

Key Considerations:

• Pre-treatment with tyrosinase inhibitors essential (4-6 weeks minimum)
• Darker skin types (Fitzpatrick IV-VI) require conservative approach
• Mandelic or lactic acid preferred for higher Fitzpatrick types
• Post-inflammatory hyperpigmentation (PIH) risk managed carefully

Australian Context: High UV exposure makes melasma management challenging. Year-round SPF 50+ essential for maintaining results. See our complete hyperpigmentation treatment guide.

Acne Scarring

Research Findings: Split-face study comparing 70% glycolic acid vs 30% TCA for atrophic acne scars found both effective. TCA showed slightly better results but increased side effects (dryness, crusting). Glycolic offered comparable improvement with less downtime.

Best Approach: Often combined with microneedling for optimal scar remodeling.