Lash, Brow & Scalp Serum Ingredients

Short answer: every LashOriginals serum is a water-based cosmetic formula built on peptides, biotin, panthenol and humectants. None of them contains a prostaglandin analogue, a free oil or a silicone. This page explains what each ingredient is actually doing, and publishes the complete INCI list for all three serums so you can check the label against the page.

Which actives are in which serum

What is acetyl tetrapeptide-3?

Acetyl tetrapeptide-3 is a synthetic four-amino-acid peptide used in leave-on cosmetic formulas. In our Lash Serum it appears alongside dextran and red clover flower extract (Trifolium pratense) — the three ingredients that make up the supplier blend sold under the trade name Capixyl. It is only in the Lash Serum; the Eyebrow and Scalp & Root serums use a different peptide.

What is biotinoyl tripeptide-1, and what is Procapil?

Biotinoyl tripeptide-1 is a short peptide with biotin attached to it, so it is both a peptide and a way of delivering biotin in a leave-on formula. It is in all three serums. Procapil is a trade name for a supplier blend of biotinoyl tripeptide-1, apigenin (a plant flavonoid) and oleanolic acid (from olive leaves), carried in butylene glycol, water, PPG-26-buteth-26 and PEG-40 hydrogenated castor oil. All seven of those appear on the INCI list of the Lash Serum and the Scalp & Root Serum. The Eyebrow Serum contains biotinoyl tripeptide-1 and oleanolic acid but not apigenin, so we do not describe it as containing Procapil.

What does biotin do in a lash or brow serum?

Biotin is vitamin B7. In a cosmetic serum it sits on the hair and skin surface as a conditioning ingredient — it is not absorbed as a dietary supplement would be, and a topical cosmetic is not a substitute for one. All three of our serums contain it, both as biotin itself and bound into biotinoyl tripeptide-1.

What is panthenol (provitamin B5)?

Panthenol is a humectant and film-former: it draws water into the hair shaft and leaves a light conditioning layer, which is why hair and lashes feel softer and look smoother after use. It is one of the most-studied conditioning ingredients in hair care and is in every LashOriginals formula.

What is sodium hyaluronate?

Sodium hyaluronate is the salt form of hyaluronic acid — a humectant that holds water. In a lash or brow serum it keeps the formula from feeling drying on the lash line and helps the product spread evenly from a fine-tip applicator.

What is hydrolyzed keratin, and is it vegan?

Hydrolyzed keratin is keratin protein broken into fragments small enough to stay in solution and deposit on the hair surface, where it smooths the cuticle. It is animal-derived — the cosmetic grade (CAS 69430-36-0) is obtained from sheep wool. That is why only our Lash Serum is vegan: the Eyebrow Serum and Scalp & Root Serum contain hydrolyzed keratin, and so do the sets that include them. Every product is cruelty-free — none is tested on animals — but cruelty-free and vegan are different claims and we keep them separate.

The Eyebrow Serum also contains hydrolyzed wheat protein, a plant protein used for the same smoothing effect. Because of it, we never describe the Eyebrow Serum as gluten-free.

What is niacinamide doing in a scalp serum?

Niacinamide is vitamin B3, used in leave-on skincare as a well-tolerated conditioning ingredient for the skin barrier. The scalp is skin, so it appears in the Scalp & Root Serum and not in the lash or brow formulas.

What are apigenin and oleanolic acid?

Apigenin is a flavonoid found in chamomile and citrus; oleanolic acid is a triterpene concentrated in olive leaves. Both are plant-derived and both are part of the Procapil blend described above. They appear low on the INCI list, which is where blend components normally sit.

What is PEG-40 hydrogenated castor oil — is the serum still oil-free?

Yes. PEG-40 hydrogenated castor oil is an ethoxylated, water-soluble solubiliser: it is what lets oil-soluble blend components dissolve in a water base. It is not a free lipid oil, it does not leave an oily film, and it does not dissolve lash-extension adhesive. There is no other oil in any of the three formulas — which is why we write "no free oils" rather than "no oils", and why the serums are suitable to use with lash extensions and after a lash lift.

What are butylene glycol and PPG-26-buteth-26?

Both are solvents and carriers. Butylene glycol dissolves the actives and helps the formula spread; PPG-26-buteth-26 is a co-solvent that arrives as part of the Procapil blend rather than being added separately. Neither is an active ingredient.

Which preservatives are used?

Phenoxyethanol with ethylhexylglycerin, plus sodium benzoate and potassium sorbate in an acid-adjusted base (citric acid). This is a standard, well-characterised preservative system for a water-based leave-on product. A water-based cosmetic that touches the eye area must be preserved — an unpreserved one is a microbiological risk, not a purity feature.

What is a prostaglandin analogue, and why isn't one in these serums?

Prostaglandin analogues are prescription-derived molecules — isopropyl cloprostenate, dechloro dihydroxy difluoro ethylcloprostenolamide, bimatoprost and relatives — that appear in some lash products sold as cosmetics. In Australia a product that claims to grow hair is a therapeutic good and must be listed on the ARTG before it is supplied or advertised; Latisse (bimatoprost) was cancelled from the ARTG in 2017. LashOriginals formulas contain none of them, which is a statement about what is on the label, not a claim about results. If you want to check any brand yourself, read its INCI list for the words above — this is exactly what our guide to reading a lash serum ingredient list walks through.

Which ingredients should I check if I have sensitive eyes?

All three serums are ophthalmologist-tested and free from prostaglandin analogues, but "well tolerated in testing" is not the same as "will suit everyone". If you have known sensitivities, the ingredients worth checking on the lists below are the preservative system (phenoxyethanol, sodium benzoate, potassium sorbate), the proteins (hydrolyzed keratin, hydrolyzed wheat protein) and the botanical extracts in the Scalp & Root Serum. Patch-test on the inner forearm before first use, and stop if irritation occurs. If you use prescription eye medicine, are pregnant or breastfeeding, or have an eye condition, speak to your doctor or optometrist first — see our safety and usage guide.

Full INCI lists

These are the complete lists, in the order printed on the pack, as required by the Australian Consumer Goods (Cosmetics) Information Standard 2020. They are identical to the lists on each product page.

Lash Serum (5 mL) — vegan

Aqua, Butylene Glycol, Glycerin, Propanediol, Phenoxyethanol, Betaine, Panthenol, Sodium Hyaluronate, Aloe Barbadensis Leaf Juice, Ethylhexylglycerin, PPG-26-Buteth-26, Biotin, PEG-40 Hydrogenated Castor Oil, Dextran, Apigenin, Citric Acid, Oleanolic Acid, Acetyl Tetrapeptide-3, Biotinoyl Tripeptide-1, Trifolium Pratense Flower Extract, Potassium Sorbate, Sodium Benzoate.

Eyebrow Serum (5 mL) — contains keratin and wheat protein

Aqua, Butylene Glycol, Glycerin, Propanediol, Phenoxyethanol, Hydrolyzed Keratin, Betaine, Panthenol, Sodium Hyaluronate, Aloe Barbadensis Leaf Juice, Ethylhexylglycerin, PPG-26-Buteth-26, Biotin, Glucose, Urea, PEG-40 Hydrogenated Castor Oil, Fructose, Hydrogenated Starch Hydrolysate, Sodium PCA, Sodium Benzoate, Citric Acid, Potassium Sorbate, Glycine, Glycolic Acid, Hydrolyzed Wheat Protein, Lactic Acid, Lysine, Malic Acid, Sodium Glutamate, Tartaric Acid, Arginine, Oleanolic Acid, Biotinoyl Tripeptide-1.

Scalp & Root Serum (50 mL) — contains keratin

Aqua, Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydrolyzed Keratin, Betaine, Panthenol, Sodium Hyaluronate, Aloe Barbadensis Leaf Juice, Ethylhexylglycerin, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Camellia Sinensis Leaf Extract, Chamomilla Recutita Flower Extract, Citrus Grandis Fruit Extract, Cocos Nucifera Fruit Extract, Gossypium Herbaceum Seed Extract, Hedera Helix Leaf Extract, Olea Europaea Leaf Extract, Rosmarinus Officinalis Extract, Salvia Officinalis Leaf Extract, Triticum Vulgare Germ Extract, Biotin, Niacinamide, Sodium Benzoate, Apigenin, Citric Acid, Oleanolic Acid, Biotinoyl Tripeptide-1, Potassium Sorbate.

What we leave out

• Prostaglandin analogues — no isopropyl cloprostenate, bimatoprost or related molecules.
• Free oils — no plant or mineral oils; the only castor-derived ingredient is the water-soluble PEG-40 solubiliser described above.
• Silicones — nothing ending in -cone or -siloxane on any of the three lists.
• Added fragrance and essential oils — no parfum on any list.
• Animal testing — none, on products or ingredients.

Where to go next

Lash Serum · Eyebrow Serum · Scalp & Root Serum · Triple Care Set

Related reading: Prostaglandin-Free Lash Serums Explained: What the Ingredient List Actually Tells You · Do Lash Serums Actually Work? What the Science Says (2026) · Safety & Usage

Sources

• Therapeutic Goods Administration — Determining if your product is a cosmetic or a therapeutic good
• Therapeutic Goods Administration — Latisse (bimatoprost) ARTG cancellation record
• ACCC Product Safety — Cosmetics ingredients labelling mandatory standard
• INCIDecoder — Procapil composition

General information about cosmetic ingredients, not medical advice. LashOriginals serums are cosmetics that condition lashes, brows and hair and support the appearance of longer-looking and fuller-looking lashes and brows. Written by the Lash Originals Editorial Team.