4D Hyaluronic Serum

Multi-Layer Hydration

Four forms of Hyaluronic Acid work together to attract and retain water at the skin's surface and within the upper layers, supporting both immediate and longer-lasting hydration.

Reduces Moisture Loss

Sodium Hyaluronate Crosspolymer creates a moisture-retaining film across the skin's surface, helping reduce transepidermal water loss and maintain hydration throughout the day.

Plumps Fine Lines & Dehydrated Skin

By increasing water content in the outer layers of the skin, Hyaluronic Acid helps temporarily plump fine dehydration lines and improve the appearance of crepey or tired-looking skin.

Supports Skin Barrier Function

Adequate hydration is essential for maintaining healthy barrier function, normal enzyme activity and the skin's ability to protect itself from environmental irritants.

Improves Skin Softness & Elasticity

Hydrated skin tends to appear smoother, more supple and more elastic. This serum helps improve the appearance of skin bounce and flexibility by replenishing moisture.

Lightweight Hydration for All Skin Types

The water-gel formula provides hydration without heavy oils or rich emollients, making it suitable for oily and congestion-prone skin as well as dry and dehydrated skin.

Supports Skin Comfort & Resilience

Particularly useful for skin experiencing tightness, dehydration or discomfort associated with insufficient moisture, helping maintain a healthier-feeling complexion.

4D Hyaluronic Acid Complex — Multi-Dimensional Hydration

Rather than one individual ingredient, this is a combination of four different forms of Hyaluronic Acid designed to work together.

Each has different molecular characteristics, influencing how it interacts with the skin and contributes to hydration.

Sodium Hyaluronate Crosspolymer — Long-Lasting Moisture Retention

A cross-linked form of Hyaluronic Acid that creates a flexible, water-retaining network across the skin's surface.

It helps form a breathable protective film that holds moisture and reduces water loss, supporting longer-lasting hydration.

Sodium Hyaluronate — Surface Hydration & Plumping

The sodium salt of Hyaluronic Acid, commonly used in skincare for its ability to bind water.

It helps maintain hydration within the outer skin layers, improving softness, suppleness and the appearance of fine dehydration lines.

Sodium Acetylated Hyaluronate — Moisture Retention & Skin Softness

A modified form of Hyaluronic Acid with an increased affinity for the skin's surface.

It adheres to the stratum corneum, helping retain moisture and improve the feeling of smoothness and softness.

Hydrolyzed Sodium Hyaluronate — Low-Molecular-Weight Hydration

A form of Hyaluronic Acid broken down into smaller molecular fragments.

Its smaller size may allow it to interact with more superficial skin structures differently from larger Hyaluronic Acid molecules, helping support hydration and the appearance of skin elasticity.

Glycerin, Propanediol & Pentylene Glycol — Additional Humectant Support

These ingredients attract and retain water, complementing the Hyaluronic Acid complex and helping maintain a comfortable, hydrated skin surface.

• Dehydrated skin of any skin type

• Dry or moisture-depleted skin

• Fine dehydration lines

• Tightness and lack of suppleness

• Dull or tired-looking skin

• Sensitive or reactive skin needing simple hydration

• Oily or acne-prone skin experiencing dehydration

  • Combination skin

  • Supporting moisture retention and barrier function

  • Skin experiencing dryness from corrective skincare

  • Those new to active skincare

  • Anyone wanting a lightweight, non-exfoliating hydrating serum

Apply 1 pump morning and/or evening to freshly cleansed skin on the face and neck, including around the eye area while avoiding direct contact with the eyes.

Gently massage or press into the skin until absorbed.

Follow with your preferred moisturiser to help maintain hydration, and broad-spectrum SPF every morning.

Can be layered with other corrective serums depending on your skin concerns and routine.

Serums are designed to deliver concentrated active ingredients to the skin to target specific concerns. While your cleanser and moisturiser support the overall health and function of your skin, a serum can add a more targeted step to your routine.

Depending on the ingredients, serums can help address concerns such as dehydration, pigmentation, breakouts, redness, oiliness and visible signs of ageing. They can also support the skin barrier and provide antioxidant protection.

Because serums are usually lightweight and formulated with a higher concentration of specific active ingredients, they can be an effective way to personalise your skincare routine around what your skin needs.

You don't necessarily need lots of serums either. The right one or two, chosen for your skin and concerns, can make a meaningful difference as part of a consistent routine.

Think of your serum as the targeted treatment step in your skincare routine — chosen to support your specific skin goals.

Professional Australian-made skincare focused on skin health, corrective care and long-term skin function.

O COSMEDICS combines skin science with functional active ingredients to create high-performance skincare designed to address a wide range of skin concerns while supporting the health of the skin barrier.

Skin First Philosophy

O COSMEDICS follows the principles of Corneotherapy, a skin treatment philosophy centred around protecting, repairing and maintaining the skin's outermost layer — the stratum corneum.

Rather than taking an aggressive approach to skincare, the range focuses on working with the skin's natural biology and supporting healthy skin function. Active ingredients and corrective treatments can then be introduced according to what the skin needs and can tolerate.

Functional Actives

O COSMEDICS products are formulated with functional doses of active ingredients selected for their ability to support specific skin functions and concerns.

These actives are used across the range to target concerns including pigmentation, acne, congestion, dehydration, inflammation, redness, loss of firmness and visible signs of ageing.

Science & Skin Health

O COSMEDICS takes a skin-health approach that considers more than just the visible appearance of the skin.

Its formulations are designed around key factors that influence skin ageing and function, including collagen breakdown, inflammation, glycation, photo damage and oxidation.

The range also incorporates biomimetic ingredients — ingredients designed to work in harmony with the skin's natural structure and processes — alongside O COSMEDICS' V8 Peptide Complex®.

Australian Made & Woman Owned

O COSMEDICS is proudly Australian made, with its products manufactured at its Sydney-based facility.

The brand was developed in Australia with the unique skin challenges of the Australian environment and climate in mind. O COSMEDICS was founded by Australian skin and beauty therapist Maria Enna-Cocciolone.

Professional Skincare

O COSMEDICS is used by professional skin therapists and clinics in Australia and internationally.

The range includes everyday skincare as well as more targeted corrective products, allowing routines to be tailored to different skin types, concerns and stages of skin health.

The goal is simple: support healthy skin, address individual concerns and achieve visible results without losing sight of the skin's long-term health.

• Free from parabens, sulfates, petrochemicals and mineral oils

• Free from artificial colours and harsh preservatives

• Free from harsh synthetic fragrances

• Vegan-friendly, gluten-free and cruelty-free

• Emulsifier-free

• Formulated with biomimetic ingredients designed to work in harmony with the skin's natural physiology

Aqua, Pentylene Glycol, Ethoxydiglycol, Glycerin, Propanediol, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydrolyzed Sodium Hyaluronate, Ethylhexylglycerin, Heptyl Glucoside, Sodium Benzoate, Potassium Sorbate, Sodium Levulinate, Citric Acid.