The Ordinary Hydrating Scalp Serum — 2 fl oz lightweight leave-in with Hyaluronic Acid & Squalane

This scalp serum blends ingredients that resemble the skin’s own moisturizing components—plus hyaluronic acid and squalane—to support the scalp’s natural barrier. Designed to be non-greasy and easily absorbed, the formula targets dryness and tightness while avoiding residue on hair strands. It’s made for daily use and formulated without silicones, alcohol, or animal-derived ingredients.

How does this serum restore moisture without weighing hair down?

The Ordinary combines natural moisturizing factors with low-molecular hyaluronic acid and lightweight squalane, which attract and retain water in the scalp layers. Because the formula is milky and fast-absorbing, it delivers hydration where it’s needed without coating hair shafts or leaving a greasy finish.

• Natural Moisturizing Factors mimic the skin’s surface lipids and amino acids.
• Hyaluronic acid pulls and holds moisture to support scalp hydration.
• Squalane provides lightweight emollience without heaviness.
• Leave-in texture absorbs quickly, preventing residue on hair.

When and how should I apply it for best results?

Use a few drops on a clean, dry scalp once daily—many users prefer applying at bedtime so the formula can work overnight. Gently massage the serum into the scalp to spread the product and stimulate circulation, then style as usual; no rinsing is required.

• Apply to clean, dry scalp for optimal absorption.
• Massage a few drops in circular motions to distribute evenly.
• Use daily, ideally at night, for continuous hydration support.
• No rinse; safe to leave in and style afterward.

What results can I expect and how quickly?

Immediate: a feeling of reduced tightness and less visible dryness on the scalp. With regular daily use, many notice improved scalp comfort and a smoother surface over weeks as the scalp barrier receives consistent hydration and support.

• Instant soothing sensation and reduced scalp discomfort.
• Progressive improvement in scalp texture with continued use.
• Helps prevent future dryness by supporting the skin barrier.
• Does not change hair volume or leave an oily finish.

Is this formula free from common irritants and suitable for sensitive skin?

The serum is formulated without silicones, alcohol, and gluten, and it’s vegan and cruelty-free, reducing the number of common irritants. However, individuals with highly reactive skin should patch-test first and consult a dermatologist if concerned.

• Silicone-free, alcohol-free, and gluten-free formula.
• Vegan and cruelty-free—no animal-derived ingredients.
• Light texture minimizes potential buildup that can irritate.
• Patch test recommended for very sensitive scalps.

Who is this for: This product is best suited for anyone experiencing dry, tight, or flaky scalp who wants a simple, lightweight leave-in treatment that won’t weigh hair down. It’s appropriate for most hair types, including fine and oily hair that needs targeted scalp hydration without sacrificing volume. If you have severe scalp conditions or suspect an underlying medical issue, seek professional advice before beginning a new topical regimen.

Ingredients

Aqua (Water), Squalane, C12-13 Alkyl Glyceryl Hydrolyzed Hyaluronate, Arginine, Aspartic Acid, Glycine, Alanine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Glutamic Acid, Glucose, Fructose, Sucrose, PCA, Sodium PCA, Zinc PCA, Magnesium PCA, Manganese PCA, Urea, Sodium Lactate, Lactic Acid, Hexyl Nicotinate, Lauryl Glucoside, Myristyl Glucoside, Polyglyceryl-6 Laurate, Isoceteth-20, Dextrin, Hexylene Glycol, Potassium Sorbate, Phenoxyethanol, Chlorphenesin.