The Ordinary Multi-Peptide Lash And Brow Serum

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

In your eyelash follicles, it activates the keratin gene and promotes nutrient absorption into the follicle. This translates to thicker and longer eyelashes over time.

Besides stimulating keratin production for lash growth, this ingredient enhances the delivery of other active ingredients in a formula.

The clinical evidence is still pretty early-stage at this point. A 90 day study in 29 participants found improvements in lash length (10.52%), volume (9.3%), thickness (35%), and curl (50.83%) with no adverse reactions reported.

You might have heard that eyelash serums can cause pigmentation change in eye color to turn eyes brown. This is associated with a different class of lash serum ingredients: prostaglandin analogs.

Myristoyl Pentapeptide-17 is a different thing entirely and has no known association with iris pigmentation changes. The 90 day study noted no adverse effects around the eye area at all.

A small human study using a mascara with 2% Biotinoyl Tripeptide-1 reported lashes that were about 17% longer and 19% thicker after one month.

One study from 2025 compared topical spray vs. a combined tropical/oral treatment. The combination group saw greater increases in total hair count.

While these early results are encouraging, most of the data comes from in-vitro experiments (in test tubes) or small, short-term trials.

Biotinoyl Tripeptide-1 looks promising for supporting hair strength and growth but there’s not yet strong clinical evidence to confirm how well it works.

The manufacturer has found combining this ingredient with red clover extract (Capixyl) boosted benefits. Not only does it enforce the scalp's extracellular matrix, it also inhibits the enzyme that creates DHT, a hormone that leads to hair loss.

While this ingredient is promising, more research is still needed to confirm its full effectiveness.

Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.

You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.

Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.

Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

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.

The glycoproteins found in skincare are most commonly derived from yeast, algae, or plant sources.

In-vitro studies have shown that yeast-derived glycoproteins can boost cellular oxygen content and increase energy production in skin cells.

In general, this is a well-tolerated humectant and skin conditioning ingredient. The Cosmetic Ingredient Review (CIR) Expert Panel has found no signs of irritation, adverse effects, or abnormal reactions from this ingredient.

The bark of Larix Europaea is rich in antioxidants and plant compounds such as flavonoids, spiro-polyphenols, and procyanidins.

Flavonoids are naturally occurring compounds found in many plantsand foods like tea, wine, and chocolate. They’re known for their strong antioxidant and anti-inflammatory properties.

Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.

In lab-grown skin models, this translated to younger, healthier, and stronger skin.

There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.

Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.

A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.

The quality of the extract matters a lot here:

Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.

Human Repeated Insult Patch Testing showed no irritation or sensitization at use concentrations (0.86% in leave-on products and up to 30% as leaf water).

As a polysaccharide, Maltodextrin has moisturizing properties. Polysaccharides are a type of carbohydrate. The top layer of skin uses polysaccharides to retain water, keeping the skin hydrated.

Maltodextrin is water soluble and has a sweet taste.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

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.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

Because it is not a free-fatty acid or alcohol, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

In its pure form, Benzoic Acid looks like a white crystalline solid. It has slight solubility in water.

The name of Benzoic Acid comes from gum benzoin, which used to be the sole source of deriving this ingredient. Benzoic Acid is the most simple aromatic carboxylic acid.

Benzoic Acid is naturally occuring in strawberries, mustard, cinnamon, and cloves. It has a slight scent but is not considered to be a fragrance.

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

Chlorphenesin is soluble in both water and glycerin.

Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.