The thought of acids used in hyperpigmentation treatment might conjure up images of lab equipment boiling over with harsh chemicals. Although skincare acids are strong and can be quite corrosive, at lower strengths, they are effective treatments that can make your skin look younger, more even, and more vibrant.
Since there are so many acids on the market today, it can be hard to know which one will work for you. This article outlines all the leading skincare acids available today and highlights each acid’s main characteristics.
Let’s dig in!
Tranexamic acid is a synthetic byproduct of lysine used as an anti-clotting drug at higher doses and an effective hyperpigmentation treatment at lower dosages.
Tranexamic acid treats melasma and other hyperpigmentation conditions like sunspots, post-inflammatory hyperpigmentation, and sun damage.
Tranexamic acid inhibits melanin production in the dermis (inner layer of the skin), reducing the amount of pigmentation that appears on the skin’s surface (epidermis).
Tranexamic acid is available in two forms: over-the-counter topical formulations and prescription-only oral tranexamic acid medication.
Azelaic acid is a naturally occurring compound found in barley, rye, and wheat with anti-inflammatory and antimicrobial properties.
Azelaic acid treats acne, acne scars, rosacea, melasma and other hyperpigmentation conditions.
When treating acne, azelaic acid cleans out the pores and keeps the skin free of bacteria, allowing it to heal and rejuvenate. When used as a skin-lightening therapy, it prevents discolored cells from multiplying.
Azelaic acid topical formulations are sold over-the-counter (<10% concentration) and through a prescription (>10% concentration).
Glycolic acid is an alpha-hydroxy acid (or AHA) found in sugarcane. Of all acids used in hyperpigmentation treatment, it has the lowest molecular weight, which allows it to penetrate deep into the skin.
Glycolic acid treats acne, acne scars, hyperpigmentation, photodamage, dryness, melasma and age-related fine lines.
Glycolic acid works in two ways: as an exfoliant, it loosens the bonds between dead skin cells on the skin’s surface, causing them to slough off easily; as a humectant, it promotes collagen production deep within the skin.
Glycolic acid is available in various low-concentration (<12%) over-the-counter topical formulations. It is also available at higher concentrations as prescription-only formulations.
Salicylic acid is a beta-hydroxy acid (BHA) derived from willow bark. As a fat-soluble acid, it penetrates deep into the skin, past the lipid layers to target deeper skin blemishes.
Low-concentration salicylic acid treats mild blackhead and whitehead acne. High-strength formulas are used as a peeling agent to treat acne, acne scars, age spots, hyperpigmentation, and melasma.
As one of the more popular acids used in hyperpigmentation treatment, it exfoliates the skin by penetrating the skin and weakening the bonds between dead surface skin cells, causing them to slough off. As a peeling agent, it rapidly dissolves cellular bonds so the top layer of skin can exfoliate faster.
Salicylic acid is sold as low-strength over-the-counter topical formulas and prescription-only high-strength topical formulations.
Kojic acid is a byproduct of various fungi that influences pigment production in the skin. Unlike other skincare acids that exfoliate, it is primarily used as a lightening agent for hyperpigmentation.
Kojic acid treats dark spots and skin discolorations in conditions like melasma, sun damage (photoaging), and post-inflammatory hyperpigmentation.
Kojic acid stops the formation of tyrosine, an amino acid crucial to the production of melanin. Halting the pigmentation process fades dark spots and discolored skin areas.
Kojic acid is used in many over-the-counter topical cosmetic products in strengths of 1% or less. It is also available as high-strength prescription-only topical formulas.
Ascorbic acid (Vitamin C/L-ascorbic acid) is a vital nutrient compound found in citrus foods with a wide range of uses inside the body and on the skin.
Topical ascorbic acid treats hyperpigmentation, dryness, sunburn, photoaging, skin sagging, wrinkles, under-eye circles, and inflammation.
Ascorbic acid’s primary mechanism is collagen production. Although the skin already gets vitamin C from your diet, topical formulas increase these levels, supporting elevated collagen production.
Topical ascorbic acid formulations from 5-15% are available OTC. Higher-strength topical formulations are available with a prescription.
Lactic acid is an alpha hydroxy acid (AHA) derived from fermenting lactose, a sugar found in milk products.
Lactic acid treats acne, acne scarring, dark spots, hyperpigmentation, photoaging, and other skin blemishes.
Acting primarily as an exfoliant, lactic acid dissolves the bond between dead skin cells on the skin’s surface, loosening them so they can easily wash off. It also has microbial and humectant properties.
Low-strength topical OTC products are available in most pharmacies. You can also get a prescription for a high-strength topical lactic acid formulation from a dermatologist.
Malic acid is a fruit acid derived from apples used in a wide range of beauty products as a pH adjuster (e.g., in shampoo), exfoliant, and humectant.
Malic acid treats acne, dry skin, photodamage, wrinkles, uneven skin tone, and hyperpigmentation conditions like post-inflammatory hyperpigmentation and melasma.
Malic acid breaks down the bonds between dead surface skin cells, improving exfoliation and skin rejuvenation. It also has humectant properties that help the skin to retain more moisture.
Malic acid is sold as low-concentration topical over-the-counter products and high-concentration prescription-only topical formulations.
As the name suggests, tartaric acid comes from ‘tart’ fruits like tamarinds and grapes. It is part of the AHA family of acids used in hyperpigmentation treatment alongside glycolic acid and lactic acid.
Tartaric acid treats dark spots, acne scars, acne, melasma, hyperpigmentation, dry skin, sun-damaged skin, and fine lines.
Tartaric acid dissolves the bonds between dead skin cells, exfoliating them to reveal newer and more vibrant skin. It also has humectant, pH balancing, and antioxidant properties.
Tartaric acid is found in many topical OTC skincare products due to its pH-balancing qualities. It is also available in higher-strength prescription-only topical formulations.
Citric acid is a potent alpha hydroxy acid derived from citrus fruits whose multifaceted properties treat a wide range of skin conditions, from alkaline skin to acne.
Citric acid clears free radicals from the skin, lightens dark spots, balances uneven skin tones, prevents wrinkles, repairs photoaging, balances skin pH, and unclogs pores.
Like other AHA’s, citric acid acts as an exfoliant that helps shed dead skin cells, as a humectant that promotes collagen production, and as an antioxidant that reduces free radicals in the skin and shields it from UV rays.
Citric acid is sold as topical OTC products with up to 15% concentration. Higher concentrations are also available as prescription-only custom topical formulations.
Acids used in hyperpigmentation treatment are generally available as OTC products that you can buy at the pharmacy or online. However, although such formulations are a great place to start using acids to treat hyperpigmentation, they tend to use low acid concentrations to make them available to a broader market. As such, they may not be as effective at treating hyperpigmentation as their prescription-strength cousins.