An oily scalp isn't a cleanliness problem — it's a sebum regulation problem. The scalp produces oil, and in some people, it produces it faster than a standard wash schedule can keep up with. The result is roots that feel greasy by the next morning, hair that loses volume and lift through the day, and a scalp environment that can become irritated and itchy as sebum accumulates between washes. Biolage Scalp Sync Oil Balancing Serum is built to address that cycle between washes rather than at the wash step alone — absorbing excess scalp oil, preventing it from migrating down the hair strand, and leaving the scalp feeling fresh and balanced for up to 48 hours.

Scalp Sync Oil Balancing Serum is an alcohol-based leave-on treatment applied to the scalp post-wash, working between shampoos to extend the life of a clean, fresh scalp environment.

Silica Silylate is the primary oil-absorbing active — a surface-treated, hydrophobic silica that works like micro-sponges at the scalp surface. Silica Silylate absorbs excess sebum as it emerges from the follicle, before it has the opportunity to migrate down the hair strand and create the weighted, flat, greasy result that oily scalp customers experience by mid-day. The surface treatment also creates a physical barrier that slows the travel of subsequent sebum down the shaft — the mechanism behind Biolage's claim that the serum keeps hair strand oil-free between washes, not just the scalp itself.

VP/VA Copolymer and Polyquaternium-11 work in concert as the formula's retention system — providing a lightweight film that keeps the Silica Silylate particles in contact with the scalp surface rather than dispersing, extending the oil-absorbing action through the day.

Saccharomyces/Xylinum/Black Tea Ferment (Fermented Tea Blend) is Biolage's hero botanical for the Scalp Sync line. Black tea fermentation produces a complex rich in antioxidants, organic acids, and beneficial microbial metabolites. Combined with Camellia Sinensis Leaf Extract (green tea), the blend provides two distinct scalp benefits: the black tea ferment's antioxidants and anti-inflammatory compounds reduce the scalp irritation and itchiness that often accompanies chronic sebum excess and follicle congestion; the green tea's catechin polyphenols provide additional antioxidant protection and help regulate the inflammatory response at the scalp's skin barrier.

Piroctone Olamine is an antifungal active — the same class of ingredient used in clinically effective anti-dandruff formulas — included here at a concentration that prevents the overgrowth of Malassezia yeast, which proliferates in sebum-rich scalp environments and is a contributing factor in scalp irritation, itchiness, and dandruff. Its presence in the INCI signals this is a clinically considered scalp treatment, not just a cosmetic serum.

Glycerin and Sorbitol provide the scalp's own humectant hydration balance — preventing the formula from making the scalp feel dry or stripped while the Silica Silylate absorbs excess oil. Ascorbic Acid (Vitamin C) provides antioxidant protection at the scalp surface.

The formula is applied from a dropper: one drop per inch across the scalp, massaged in for one minute post-wash, then dried as normal without rinsing.

Paraben-free. Silicone-free. Mineral oil-free. Colorant-free. Vegan. Leaping Bunny certified cruelty-free.

Metro Vancouver note: Coastal humidity drives scalp warmth and sebum dysregulation — the warm, damp conditions of Metro Vancouver's Pacific climate are among the most common environmental triggers for accelerated sebum production year-round. A leave-on scalp serum applied after washing extends the time between grease-heavy hair days without requiring more frequent washing — which typically worsens the sebum rebound cycle. See our Scalp Health hub for the full oily scalp diagnostic.

Who It's For Oily or combination scalp — all hair types and textures. Suitable for daily use post-wash. Compatible with all hair care routines, not just the Scalp Sync line, though results are optimised when used as Step 4 of the full Scalp Sync system. Safe for colour-treated hair. Suitable for use on scalps with 100% human hair extensions (apply to scalp only, avoiding adhesion points).

Best results as part of the complete Scalp Sync oily scalp routine: Scalp Sync Purifying Concentrate → | Scalp Sync Clarifying Shampoo → | Scalp Sync Universal Conditioner → 

Key Ingredients

• Silica Silylate — Surface-treated hydrophobic silica; absorbs excess sebum at the follicle surface and prevents oil migration down the hair strand
• Saccharomyces/Xylinum/Black Tea Ferment (Fermented Tea Blend) — Antioxidant-rich fermented black tea; reduces scalp irritation and itchiness associated with chronic sebum excess
• Camellia Sinensis Leaf Extract (Green Tea) — Catechin polyphenols; provides antioxidant protection and supports the scalp's inflammatory response regulation
• Piroctone Olamine — Antifungal active; prevents Malassezia yeast overgrowth in sebum-rich scalp environments; reduces irritation and dandruff-adjacent scalp concerns
• VP/VA Copolymer & Polyquaternium-11 — Lightweight film-forming system; keeps Silica Silylate in contact with the scalp surface to extend oil-absorbing action through the day
• Glycerin & Sorbitol — Humectants; maintain the scalp's own hydration balance while oil is being absorbed

How to Use Apply post-wash to a clean, wet scalp. Drop one drop per inch across the scalp surface. Massage gently for one minute to distribute evenly. Dry hair and scalp as usual — do not rinse. Avoid contact with eyes. Use after every wash for continuous between-wash oil control.