Medik8 C-TETRA® | Vitamin C Serum | 30ml

Additional Product Information

Size: 30ml (up to 6 months supply with daily use)

Texture: Lightweight, silky oil-based serum with rapid absorption and non-greasy finish

Skin Type Suitability: All skin types, particularly suitable for sensitive skin and vitamin C beginners

Clinical Testing: Independent consumer study conducted over 4 weeks on 52 participants with sensitive skin demonstrating proven efficacy and gentleness

Free-From Claims: No artificial fragrance, no synthetic colours, paraben-free, certified vegan by The Vegan Society, cruelty-free

Packaging: Amber glass bottle with pipette applicator to protect the stable formula and ensure precise dosing

Special Notes

Certifications: Certified by The Vegan Society; B Corp certified brand

Free-From Status: Vegan, cruelty-free, paraben-free, no artificial fragrance, no synthetic colours

Storage Requirements: Store in a cool, dry place away from direct sunlight. The stable formula maintains potency for up to 6 months after opening when stored correctly

Unique Features: 100% stable vitamin C formula that doesn't oxidise or degrade over time; manufactured in the UK at an ISO-certified Innovation Centre; part of Medik8's pioneering CSA Philosophy for comprehensive anti-ageing care

How To Use

Application: After cleansing in the morning, dispense 4 drops of C-TETRA® into the palm of your hand. Gently massage across the face, neck and décolletage using upward motions

Frequency: Apply once daily every morning as part of your CSA Philosophy skincare routine

Timing: Use after cleansing and before applying sunscreen and moisturiser. Allow the serum to absorb fully (approximately 1-2 minutes) before layering additional products

Layering: C-TETRA® layers beautifully beneath sunscreen and moisturiser. For enhanced age-defying results, we especially recommend pairing with Medik8's Advanced Day Total Protect SPF 30 during the day, and incorporating a vitamin A product such as Crystal Retinal at night as part of the complete CSA Philosophy

Expert Tips: For optimal results, always follow with a broad-spectrum SPF 30 or higher, as vitamin C and sunscreen work synergistically to provide ultimate protection against environmental ageing. Patch testing prior to use is advised

Full Ingredients List

Simmondsia Chinensis (Jojoba) Seed Oil, Cyclopentasiloxane, Cyclohexasiloxane, Tetrahexyldecyl Ascorbate, Citrus Grandis (Grapefruit) Peel Oil, Tocopheryl Acetate, PPG-12/SMDI Copolymer, Limonene, Citral, Linalool, Geraniol.

Please note: Formulations are updated periodically by manufacturers without notice. Therefore, the ingredient lists on this website may differ from the product packaging depending on the time and country of purchase. Please refer to your product packaging for accurate ingredient lists. A patch test before use must be carried out for suitability.

FAQ

Q: Is C-TETRA® suitable for sensitive skin and first-time vitamin C users?

A: Absolutely. C-TETRA® is specifically formulated with tetrahexyldecyl ascorbate, a stabilised form of vitamin C that is exceptionally gentle on sensitive skin. Clinical studies show that 96% of sensitive skin participants found C-TETRA® gentle on their skin, and 87% agreed it was the most gentle vitamin C serum they had ever used. This makes it the perfect introduction to vitamin C skincare without the irritation often associated with traditional ascorbic acid formulations.

Q: How quickly can I expect to see results from using C-TETRA®?

A: Independent clinical studies demonstrate that visible improvements in skin radiance can be observed in as little as 7 days with consistent daily use. After 4 weeks of regular application, participants experienced visibly reduced wrinkles and dark spots, with 90% agreeing their skin felt instantly softer. For optimal long-term benefits including collagen stimulation and comprehensive antioxidant protection, our experts recommend continued daily use as part of your morning skincare routine.

Q: Can I use C-TETRA® alongside other active ingredients like retinol or vitamin A?

A: Yes, C-TETRA® is designed to complement other active ingredients perfectly. It forms the foundation of Medik8's CSA Philosophy – vitamin C plus Sunscreen by day, vitamin A (retinoids) by night. Apply C-TETRA® in your morning routine, always followed by sunscreen, and use your vitamin A product in the evening. This strategic approach addresses 90% of anti-ageing skincare needs. If you have specific concerns about layering products, speak to our skincare experts for personalised guidance.

Q: Why does C-TETRA® have an oil-based texture rather than a water-based formula?

A: The jojoba seed oil base serves multiple important functions. Firstly, it provides the ideal delivery system for the lipid-soluble tetrahexyldecyl ascorbate, allowing optimal penetration into the skin. Secondly, the oil-free, water-free formula ensures 100% stability – the vitamin C cannot oxidise or degrade over time, maintaining full potency for up to 6 months after opening. Finally, jojoba oil closely mimics the skin's natural sebum, providing lightweight nourishment and an immediate luminous glow without clogging pores or feeling greasy.

Q: How long will a 30ml bottle of C-TETRA® last?

A: With the recommended usage of 4 drops per application once daily, a full-size 30ml bottle provides up to 6 months supply, offering exceptional value for a professional-grade vitamin C serum. The precise pipette applicator ensures accurate dosing and prevents product waste.