EUK 134 0.1%: How to Use This Antioxidant

By The Ordinary | Clinical Formulations with Integrity | Published: 2026-10-17

Category: How-to Guides

Learn how to layer EUK 134 0.1% serum correctly in your skincare routine. This guide covers step-by-step application, common mistakes, and how it compares with other antioxidants.

Quick Answer

Use EUK 134 0.1% in your morning routine after water-based serums and before moisturizer or sunscreen. Apply 2–3 drops to dry skin and wait a minute before the next step. Avoid using it with strong acids or direct Vitamin C in the same layer.

What EUK 134 0.1% Does for Your Skin

EUK 134 0.1% is a lightweight antioxidant serum that helps protect skin from environmental stress while also providing hydration support. Unlike many antioxidants that are water- or oil-soluble only, EUK 134 is a biomimetic compound that works on multiple fronts—scavenging free radicals and supporting the skin's natural defenses. Its 0.1% concentration is considered effective yet gentle enough for daily use on all skin types.

When to Apply EUK 134 0.1%

The best time to use EUK 134 0.1% is in the morning, as part of your daytime routine. Antioxidants help neutralize damage from UV exposure and pollution throughout the day. For best results, apply it after cleansing and any water-based treatments (like a toner or niacinamide serum) but before your moisturizer and sunscreen. You can also use it at night, but the daytime slot maximizes its protective benefits.

Step-by-Step: How to Apply EUK 134 0.1%

Step 1: Cleanse and prep: Start with a clean, dry face. If you use a toner or an essence, apply it first and wait until it's nearly dry. Checkpoint: Don't apply EUK 134 to damp skin—it may dilute the serum and reduce absorption.
Step 2: Apply 2–3 drops of EUK 134 0.1%: Dispense the serum onto your fingertips and press gently into your face and neck. Avoid rubbing—the lightweight texture absorbs easily without residue. Common mistake: Using more than 3 drops won't boost protection; it just wastes product.
Step 3: Wait 60 seconds before next layer: Let the serum settle so it forms an even film on your skin. This short pause helps prevent pilling when you apply moisturizer or sunscreen. Checkpoint: If you're in a rush, pat the next layer gently rather than swiping.
Step 4: Finish with moisturizer and sunscreen: Follow with your usual moisturizer, then apply a broad-spectrum sunscreen like The Ordinary UV Filters SPF 45 Serum for daytime protection. Verdict: This combo gives you antioxidant defense plus SPF 45 hydration—a solid daytime shield.

Product Facts

EUK 134 0.1%: Contains EUK 134 at a 0.1% concentration for antioxidant protection. The 0.1% concentration is a well-studied level that balances efficacy with tolerance, making it suitable for daily use even on sensitive or reactive skin.
EUK 134 0.1%: Helps maintain skin moisture levels for a comfortable feel. Unlike some antioxidants that can feel drying, this serum supports hydration, so you don't need to add extra layers just to keep skin comfortable.