The Derma Co 5% Glycolic + 2% Kojic Pigmentation Corrector Ampoule Kit

PH adjusters are common in cosmetic products. The pH of a product can affect the effectiveness of other ingredients. A product with a high pH may also irritate the skin.

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The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

Ethoxydiglycol also helps deliver other key ingredients into the skin.

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

By latching onto the copper that the enzyme tyrosinase needs to function, Kojic Acid prevents less pigment from being made. It's so well-established that researchers regularly use it as the go-to benchmark when testing new brightening ingredients.

Some other perks include documented antioxidant and antimicrobial properties. The The CIR (Cosmetic Ingredient Review) Expert Panel concluded Kojic Acid is safe for use in cosmetic products at concentrations up to 1% and the EU's SCCS (Scientific Committee on Consumer Safety) considers it safe as a skin lightening agent at concentrations up to 0.7%.

One thing to know about Kojic Acid is that stability is its weak spot; it is sensitive to light, heat, and air exposure and will oxidize/turn brown in formulations. Its derivative, Kojic Dipalmitate, was developed as a stable alternative.

Some individuals have reported contact sensitization so be sure to patch test if you have reactive or sensitive skin.

Fun fact: It was first discovered in 1907 and naturally occurs in the production of sake, soy sauce, and miso.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.