Medik8 C-Tetra - 30ml

Does your skin look dull, with early fine lines and uneven tone? Then Medik8 C-Tetra (an antioxidant vitamin C serum) is the logical first step in your morning routine. It contains 7% lipid vitamin C in an oil-based formula that is stable and non-irritating, making it suitable for all skin types – including sensitive skin. As the C in the Medik8 CSA philosophy, C-Tetra lays the foundation: vitamin C and sun protection by day, vitamin A at night.

How it works

Tetrahexyldecyl Ascorbate is the oil-soluble, stable form of vitamin C. It penetrates deep into the skin and stimulates collagen production in the fibroblasts, resulting in a firmer extracellular matrix that helps fill fine lines and wrinkles. Its powerful antioxidant action defends against free radicals and environmental stress while helping to fade pigmentation spots and discolouration. Tocopheryl Acetate (vitamin E) supports the antioxidant defence, while Simmondsia Chinensis (Jojoba) Seed Oil keeps the formula nourishing and comfortable.

Texture and use in your routine

The texture is lightweight and oil-based, absorbs quickly and carries a fresh citrus note from grapefruit peel oil. That light feel makes C-Tetra especially pleasant for oily skin. Apply the serum in the morning after cleansing and before your moisturiser, always followed by an SPF 30 or higher – for example Advanced Day Ultimate Protect SPF 50+. In the evening, pair with a vitamin A product from the Crystal Retinal range. The serum also supports the results of skin rejuvenation treatments such as chemical peels, medical needling and IPL.

Frequently asked questions

Which step of the CSA routine is C-Tetra?

C-Tetra is the C: apply it in the morning to cleansed skin, then follow with moisturiser and SPF. At night you use vitamin A.

Can I combine C-Tetra with Crystal Retinal?

Yes. Medik8 recommends vitamin C in the morning and retinal in the evening so both actives can work at their best.

Is C-Tetra suitable for sensitive skin?

Yes, the stable lipid form of vitamin C is gentle and non-irritating. With sensitive skin, start once a day and build up slowly.

C-Tetra delivers 7% lipid vitamin C as Tetrahexyldecyl Ascorbate. This oil-soluble, stable form is optimally absorbed by the skin, penetrates deeply and stays effective for longer. Within the skin, vitamin C stimulates collagen production in the fibroblasts, creating a firmer extracellular matrix that helps fill fine lines and wrinkles. At the same time, its powerful antioxidant action shields the skin from free radicals and environmental stress and helps fade pigmentation spots and discolouration. Vitamin E and jojoba oil support the formula and keep skin comfortable.

In the morning, apply a few drops to cleansed skin and gently massage over face and neck, before your moisturiser. Always follow with an SPF 30 or higher. If your skin is sensitive, start with once a day and build up slowly. In the evening, combine with a vitamin A product from the Crystal Retinal range to complete your CSA routine.

After a few weeks of daily use, skin looks visibly more radiant and even. Fine lines appear softer, texture is refined and pigmentation spots and discolouration gradually fade. Your skin is also better protected day to day against free radicals and environmental stress.

• Vitamin C – Stimulates collagen production, protects against free radicals, and brightens the complexion
• Vitamin E – A powerful antioxidant that protects against free radicals and premature skin aging
• Jojoba oil – Rich in fatty acids, it has a soothing effect and supports skin recovery.

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

The manufacturer is responsible for the composition of the product. As the composition may change, we recommend always checking the ingredients on the packaging.