Medik8 C-Tetra Vitamin C Face Serum — 1.0 fl oz Lightweight Daily Serum with Hyaluronic Acid & Squalane

Medik8 C-Tetra is a lightweight, stabilized vitamin C facial serum with multi-weight hyaluronic acid designed to brighten skin and support hydration when used each morning.

Designed around Medik8’s CSA philosophy, this daily serum combines a stable form of vitamin C with hydrating ingredients and antioxidant technologies to help skin appear smoother, more luminous, and comfortable throughout the day. The formula is vegan, suitable for a range of skin types including sensitive skin, and pairs with sunscreen as part of a daytime routine for antioxidant support.

How does this serum help skin look brighter and more even?

The stabilized vitamin C in C-Tetra delivers antioxidant support that can enhance skin radiance and the appearance of uneven tone. Consistent morning use helps protect skin against environmental stressors while promoting a refreshed surface appearance.

• Stabilized vitamin C ingredient for lasting activity.
• Antioxidant-rich formulation to support surface brightness.
• Light texture absorbs quickly to layer under SPF.

What hydration benefits does Medik8 C-Tetra offer?

Multi-weight hyaluronic acid hydrates at different skin levels, while squalane and phyto exosomes help maintain comfort and softness. Together these ingredients reduce the look of dryness and give skin a plumper visual texture.

• Low-, medium- and high-weight hyaluronic acids for layered hydration.
• Squalane to help preserve skin’s softness and barrier feel.
• Phyto exosomes to support an overall healthy-looking complexion.

Can I use this every morning with my sunscreen?

Yes — C-Tetra is formulated specifically for morning use and is lightweight enough to layer under sunscreen or makeup. Applying it before SPF complements sun protection by adding antioxidant defense during daytime exposure.

• Apply 2–3 drops to face and neck after cleansing and before SPF.
• Fast-absorbing serum that won’t pill under sunscreen.
• Works with various sunscreen textures, from creams to fluids.

Is this suitable for sensitive skin?

The formula is developed to be gentle while still effective: a stabilized vitamin C form and a hydrating base reduce the likelihood of irritation compared with some stronger vitamin C actives. Patch testing is recommended for very reactive skin, but many find this serum comfortable for daily use.

• Vegan formula designed for a variety of skin types.
• Stabilized vitamin C chosen for tolerability.
• Hydrators help soothe and reduce tightness.

Who is this for: Medik8 C-Tetra is aimed at anyone seeking a daily, non-greasy vitamin C serum that supports radiance and hydration — ideal for people wanting antioxidant support with an easy morning application. It suits beginners to vitamin C and those with normal, combination, dry, or sensitive skin looking to pair a brightening serum with sunscreen as part of a science-backed daytime routine.

Ingredients

Water, Tetrahexyldecyl Ascorbate, Isododecane, Propanediol, Acetyl Glucosamine, Squalane, Tocopherol, Acetyl Zingerone, Camellia Sinensis (Green Tea) Leaf Vesicles, Hydroxyacetophenone, Sodium Hyaluronate, Cellulose, Avena Sativa (Oat) Kernel Extract, Glycerin, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Citrus Grandis (Grapefruit) Peel Oil, Sucrose Stearate, Tetrasodium Glutamate Diacetate, Ethylhexylglycerin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Xanthan Gum, Sodium Benzoate, Cellulose Gum, 1,2-Hexanediol, Polysorbate 60, Sorbitan Isostearate, Citric Acid, Phenoxyethanol, Citral, Linalool, Limonene