Mandelic Acid
The gentlest AHA, derived from bitter almonds. Mandelic acid has the largest molecular size of commonly used AHAs (152 Da), giving it the slowest skin penetration and the least irritation potential. It is also lipophilic (partially oil-soluble), giving it some ability to penetrate pores — a property unique among AHAs. Especially effective for acne-prone skin with hyperpigmentation, and safe for darker skin tones.
Concentration & Usage
Concentrations: 5-10% for daily use. 25-40% for professional peels. Can be used daily with minimal irritation for most skin types. Particularly effective for skin of color (Fitzpatrick IV-VI) due to lower risk of post-inflammatory hyperpigmentation.
Application
Topical (serum, peel, toner). Safe for daily use. Apply at night.
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99%+ purity · third-party lab tested
Mechanism of Action
Mandelic acid (152 Da, the largest common AHA) exfoliates through calcium chelation and corneodesmosome disruption like other AHAs, but its large molecular size results in slower, more even epidermal penetration with reduced risk of hot-spot irritation and stratum corneum over-exfoliation. Its phenyl ring confers partial lipophilicity, enabling penetration into the pilosebaceous unit and follicular infundibulum—unlike purely hydrophilic glycolic and lactic acids. Within pores, mandelic acid exerts mild comedolytic effects by disrupting keratinocyte cohesion in the follicular epithelium, similar to salicylic acid. It demonstrates antibacterial activity against Cutibacterium acnes (Propionibacterium acnes) through membrane disruption. Mandelic acid also inhibits tyrosinase and reduces melanosome transfer to keratinocytes, providing brightening benefits. This profile makes it particularly suitable for acne-prone skin, hyperpigmentation, and darker skin tones (Fitzpatrick IV–VI) where gentler exfoliation minimizes post-inflammatory hyperpigmentation risk.
Ingredient Interactions
Mandelic acid is gentler than glycolic but still an AHA. Separate from vitamin C to avoid pH stacking. Vitamin C in AM, mandelic acid at PM.
See our full Ingredient Interactions Guide for more combinations and timing strategies.
Regulatory Status
Cosmetic ingredient. Available OTC worldwide.
Risks & Safety
Common
Very mild — less irritating than any other AHA. Slight tingling.
Serious
None.
Rare
Contact dermatitis. Cross-reactivity in people with almond allergies is theoretically possible but unconfirmed.
Compare Mandelic Acid With
Research Papers
10Published: April 30, 2020
AI Summary
It is common in adolescents and primarily affects sebaceous gland-rich areas. The clinical benefit of the topical acne treatments azelaic acid, salicylic acid, nicotinamide, sulphur, zinc, and alpha-hydroxy acid is unclear.
Published: December 3, 2018
AI Summary
After four weeks of topical mandelic acid treatment, the elasticity of lower eyelid skin increased 25.4% (P = .003). Improvement in photographic appearance correlated with these findings.
Published: October 26, 2017
AI Summary
In acne scars, chemical peels may be combined with other procedures to achieve better clinical results. A series of chemical peels can lead to significant improvement over a short period, leading to patient satisfaction and maintenance of clinical results. © 2016 Elsevier Inc.
Published: September 15, 2025
AI Summary
This study investigated the enhanced skin permeation and pigmentation reduction effects of an ion-pair complex formed between tranexamic acid (TXA) and mandelic acid (MA). The TXA-MA complex demonstrated superior skin permeability and greater inhibition of cytokine expression compared to TXA alone,
Published: March 9, 2016
AI Summary
Treatment of this condition is difficult and associated with high recurrence rates. Chemical peels have become a popular modality in the treatment of melasma.
Published: February 13, 2023
AI Summary
Further, results confirmed that the addition of mandelic acid had a desirable effect on gel properties (antimicrobial, consistency, stability). It has been shown that the essential oil/mandelic acid combination can be a dermatologically beneficial hand sanitiser compared to commercial products.
Published: January 7, 2009
AI Summary
Many clinicians have used glycolic acid (GA) peels for facial acne, scarring, and hyperpigmentation, mainly in lighter skin types. Salicylic-mandelic acid combination peels (SMPs) are a newer modality, and there have been no well-controlled studies comparing them with other conventional agents.
Published: September 22, 2024
AI Summary
Sensory analysis revealed that the matrix containing Mandelic Acid alone or combined with Litsea Cubeba Oil was the best-performing formulation, consistent with the compliant results of antimicrobial efficacy. The topical form of this cosmetic product has demonstrated excellent preservative activity and desirable biophysical efficacy on the skin.
Published: February 29, 1992
AI Summary
The first and second groups showed values of HVA and VMA from 4 to 10 times and from 1/2 to 3 times higher respectively than those of controls, while no significant differences were found between the third group and controls.
Published: February 8, 2023
AI Summary
Actually, the use of chemical peels in cosmetics and dermatology continues to grow due to their versatility, clinical endpoint-directed predictability, and favorable risk profile in comparison to lasers. The major challenge of chemical peels is the tolerability, that is because of sensitive skin which is one of the most common skin disorders.
Frequently Asked Questions
What is Mandelic Acid used for?
The gentlest AHA, derived from bitter almonds. Mandelic acid has the largest molecular size of commonly used AHAs (152 Da), giving it the slowest skin penetration and the least irritation potential. It is also lipophilic (partially oil-soluble), giving it some ability to penetrate pores — a property unique among AHAs. Especially effective for acne-prone skin with hyperpigmentation, and safe for darker skin tones.
What are the side effects of Mandelic Acid?
Common: Very mild — less irritating than any other AHA. Slight tingling. Serious: None. Rare: Contact dermatitis. Cross-reactivity in people with almond allergies is theoretically possible but unconfirmed.
How is Mandelic Acid administered?
Mandelic Acid is administered via topical (serum, peel, toner). safe for daily use. apply at night..
Related Nootropics
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Adapalene
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Alpha Arbutin
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Azelaic Acid
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Azelaic Acid
A dicarboxylic acid naturally produced by Malassezia yeast on human skin. Azelaic acid is a uniquely versatile ingredient — it treats acne, reduces hyperpigmentation, has anti-rosacea effects, and is safe in pregnancy. It selectively targets abnormally active melanocytes while leaving normal pigmentation alone, making it ideal for post-inflammatory hyperpigmentation. Also available by prescription (15-20%) for rosacea.
Benzoyl Peroxide
The most effective OTC acne treatment and one of the few topical treatments that kills acne-causing bacteria (C. acnes) without promoting antibiotic resistance. Benzoyl peroxide works through oxidation — it releases oxygen into pores, creating an environment where anaerobic bacteria cannot survive. It is one of three first-line acne treatments (alongside adapalene and salicylic acid) recommended by dermatological guidelines.