The Complete Guide to Facial Peels — From Superficial to Deep

Last updated: 5 March 2026

Chemical peels remain one of the most established and evidence-based treatments in aesthetic dermatology. From gentle lunchtime peels to transformative deep peels, these treatments use carefully selected acids to remove damaged skin layers and stimulate renewal. This comprehensive guide explores every aspect of facial peels available in the United Kingdom, helping you understand which type may be most appropriate for your skin concerns.

What Is a Chemical Peel?

A chemical peel involves the controlled application of an acid solution to the skin surface. This causes a predictable, uniform exfoliation of damaged skin cells, triggering the body’s wound-healing response. As the treated skin peels away over the following days, it is replaced by healthier, smoother, and more evenly pigmented skin from beneath.

The depth of the peel determines both the intensity of the results and the recovery time required. Peels are classified into three categories based on the depth of skin penetration: superficial (epidermis only), medium (papillary dermis), and deep (reticular dermis). Each category uses different active agents at varying concentrations and pH levels.

Types of Chemical Peels

Superficial Peels

Superficial peels target only the outermost layer of skin — the epidermis. They are the gentlest option and are often referred to as “lunchtime peels” because they require minimal to no downtime. These peels are ideal for mild skin concerns and general skin maintenance.

Common superficial peel agents include glycolic acid (20-50%), salicylic acid (20-30%), lactic acid (10-30%), mandelic acid (30-50%), and low-concentration trichloroacetic acid (TCA) at 10-20%. Treatment sessions typically last 15-30 minutes, with mild tingling or warmth during application.

Medium-Depth Peels

Medium peels penetrate through the epidermis into the upper dermis (papillary dermis). They produce more significant results than superficial peels but require several days of recovery. TCA at 35-50% concentration is the most commonly used medium-depth peel agent, sometimes combined with Jessner’s solution for enhanced penetration.

Medium peels are effective for moderate sun damage, age spots, fine-to-moderate wrinkles, and mild acne scarring. The treated skin typically develops a frosted white appearance during the procedure, followed by significant redness, swelling, and peeling over 5-10 days.

Deep Peels

Deep peels penetrate into the mid-reticular dermis and produce the most dramatic results. Phenol (Baker-Gordon formula) is the primary agent used for deep peels. Due to the intensity of treatment and potential systemic absorption, deep peels require cardiac monitoring, intravenous sedation or general anaesthesia, and are performed exclusively by experienced dermatologists or plastic surgeons.

Deep peels can significantly improve deep wrinkles, severe sun damage, and pronounced pigmentation irregularities. However, they carry higher risks and require 2-4 weeks of intensive recovery. In the UK, deep peels are relatively uncommon compared to superficial and medium-depth options, with many practitioners preferring fractional laser resurfacing as an alternative for deep skin concerns.

Peel Depth	Common Agents	Target Layer	Recovery Time	Typical Cost (UK)
Superficial	Glycolic, Salicylic, Lactic, Mandelic	Epidermis	0-3 days	£80-£200
Medium	TCA 35-50%, Jessner’s + TCA	Papillary dermis	5-10 days	£200-£500
Deep	Phenol (Baker-Gordon)	Reticular dermis	2-4 weeks	£1,000-£3,000

Understanding Peel Acids: A Detailed Breakdown

Alpha Hydroxy Acids (AHAs)

AHAs are water-soluble acids derived from natural sources. Glycolic acid (from sugar cane) has the smallest molecular size, allowing deepest penetration. Lactic acid (from milk) is gentler and provides hydrating benefits alongside exfoliation. Mandelic acid (from almonds) has the largest molecular size, making it the gentlest AHA — ideal for sensitive skin and darker skin tones where post-inflammatory hyperpigmentation is a concern.

Beta Hydroxy Acids (BHAs)

Salicylic acid is the primary BHA used in chemical peels. Being oil-soluble, it penetrates into sebaceous follicles, making it particularly effective for acne-prone and oily skin. Salicylic acid also possesses anti-inflammatory properties that help calm active breakouts during the peeling process.

Trichloroacetic Acid (TCA)

TCA is the most versatile peel agent, capable of producing superficial to medium-depth effects depending on concentration and application technique. At lower concentrations (10-20%), TCA produces a gentle superficial peel. At 35-50%, it creates a medium-depth peel with visible frosting. TCA is self-neutralising, meaning it does not require a neutralising agent, which gives the practitioner precise control over the depth of penetration.

Jessner’s Solution

This combination peel contains salicylic acid, lactic acid, and resorcinol in an ethanol base. It is often used as a priming agent before TCA application to ensure more uniform penetration. The Jessner’s + TCA combination (known as the “Monheit peel”) is one of the most popular medium-depth protocols worldwide.

Skin Concerns Addressed by Chemical Peels

Chemical peels can effectively treat a wide range of skin concerns, though the appropriate peel type varies depending on the condition. Hyperpigmentation and melasma respond well to superficial peels containing kojic acid or azelaic acid combinations. Acne and acne scarring benefit from salicylic acid peels and medium-depth TCA peels respectively. Fine lines and wrinkles are best addressed with medium-depth peels, whilst sun damage and photoageing may require a series of superficial peels or a single medium-depth treatment.

Skin Types and Peel Selection

The Fitzpatrick skin type classification is crucial in peel selection. Patients with darker skin tones (Fitzpatrick IV-VI) carry a higher risk of post-inflammatory hyperpigmentation (PIH) following chemical peels. For these patients, superficial peels with mandelic acid or low-concentration glycolic acid are preferred, with careful pre-treatment priming using topical retinoids and hydroquinone alternatives such as tranexamic acid or arbutin.

The Treatment Process

Pre-Peel Preparation

Optimal peel results require appropriate skin preparation. Most practitioners recommend a 2-4 week pre-peel regimen that may include daily use of a broad-spectrum SPF 50 sunscreen, introduction of topical retinoids to normalise skin cell turnover, use of tyrosinase inhibitors for patients with pigmentation concerns, and discontinuation of isotretinoin (Roaccutane) at least 6 months prior.

During the Peel

The skin is thoroughly cleansed and degreased before application. The acid solution is applied systematically, often starting with the forehead and working downwards. The practitioner monitors the skin’s response closely, watching for colour changes and frosting patterns that indicate the depth of penetration. Superficial peels are typically left on for 1-5 minutes, whilst medium peels may require multiple coats to achieve the desired depth.

Post-Peel Care

Aftercare is critical to achieving optimal results and preventing complications. For superficial peels, a gentle cleanser, hydrating moisturiser, and SPF 50 sunscreen are usually sufficient. Medium peels require more intensive care, including petroleum-based ointments to maintain wound moisture, avoidance of sun exposure for 2-4 weeks, and careful monitoring for signs of infection. Patients must resist the temptation to pick or peel flaking skin, as premature removal can lead to scarring and pigmentation changes.

Risks and Complications

When performed by qualified practitioners, chemical peels have an excellent safety profile. However, potential complications include post-inflammatory hyperpigmentation (particularly in darker skin tones), persistent erythema (redness lasting beyond the expected healing period), bacterial or viral infection (herpes simplex reactivation is a known risk), allergic or sensitivity reactions, and scarring (extremely rare with superficial peels, more common with deep peels).

To minimise risks, patients should disclose their full medical history, including any history of cold sores, keloid scarring tendency, current medications, and recent cosmetic treatments. Antiviral prophylaxis with aciclovir may be prescribed for patients with a history of herpes simplex before medium or deep peels.

UK Regulatory Framework

In the United Kingdom, chemical peels using high-concentration acids are considered medical procedures and should be performed by or under the supervision of qualified medical professionals. The Joint Council for Cosmetic Practitioners (JCCP) and the Cosmetic Practice Standards Authority (CPSA) provide guidelines for safe practice. Clinics performing medium and deep peels should be registered with the Care Quality Commission (CQC) in England.

Superficial peels using lower acid concentrations may be performed by trained aestheticians, though medical oversight is recommended. The Save Face register, accredited by the Professional Standards Authority, helps patients identify safe and reputable practitioners.

Combining Peels with Other Treatments

Chemical peels can be effectively combined with other aesthetic treatments as part of a comprehensive skin rejuvenation programme. Popular combinations include peels with microneedling (performed at separate sessions, typically 2-4 weeks apart), peels with LED light therapy (can often be performed on the same day), and peels with injectable treatments (botulinum toxin and fillers should be performed at least 2 weeks before or after a peel).

Frequently Asked Questions

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