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C-Tetra®

Medik8 C-Tetra® 30ml

%0 4.73 | 907 reviews
Box

£45.00 (£1.50 per ml)

Free UK delivery

In stock

If you like we can let you know when we have some more.

Product Description

Restore the appearance of skin radiance in just 7 days* with Medik8’s cult favourite C-Tetra serum.

Expertly formulated by their skincare experts with a stabilised form of vitamin C (tetrahexyldecyl ascorbate ), this lightweight serum reduces the appearance of fine lines and wrinkles and visibly brightens uneven skin tone - all while remaining gentle on sensitive skin.

The addition of antioxidant-rich vitamin E protects the skin against the damaging and ageing effects of free radicals for a more healthy, youthful-looking complexion overall. The perfect daily serum for those who are new to vitamin C, or have sensitive skin.
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Key Benefits:
Increased Skin Youthfulness
Proven to smooth the appearance of fine lines and wrinkles and visibly boost skin's radiance in 7 days*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Brighter, More Even Complexion
Proven to visibly brighten the skin in 7 days* and reduce the appearance of wrinkles & dark spots in 4 weeks*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Gentle, Lightweight Nourishment
The jojoba seed oil-based formula delivers non-greasy yet effective nourishment for visibly comforted and softer skin.
87% of sensitive skins agree this is the most gentle vitamin C serum they have ever used*
96% of sensitive skins agreed C-Tetra was gentle on the skin*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Proven Results:
7 days to restored skin radiance*
7 days to visibly brighter
96% of sensitive skins agreed C-Tetra was gentle on the skin*
4 weeks to visibly reduced wrinkles & dark spots*
90% agree skin feels instantly softer*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Key Ingredients:
Stabilised Vitamin C (tetrahexyldecyl ascorbate)
This stable, low-irritation form of vitamin C is incredibly effective on the skin; delivering exceptional protection against ageing free radicals. Supporting collagen production and brightening the skin tone, it leaves the complexion visibly more even, radiant and youthful-looking.

Vitamin E
Rich in antioxidants, vitamin E helps to protect the skin against ageing free radicals. It also helps to boost the power of vitamin C for maximum visible results.

Good to Know:
NO ARTIFICIAL FRAGRANCE
NO SYNTHETIC COLOURS
PARABEN FREE
CERTIFIED BY THE VEGAN SOCIETY

Directions

STEP 1
After cleansing in the morning, massage 4 drops across the face, neck and décolletage.

STEP 2
Leave to absorb before applying sunscreen. We recommend Advanced Day Ultimate Protect.

How to Layer C-Tetra
AM: Apply C-Tetra after cleansing and toning in your morning skincare routine. Always follow with sunscreen.

Ingredients

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

This list of ingredients may be subject to change, please consult the packaging of the product purchased.

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Rated 5 out of 5 by from My new go to! Need [This review was collected as part of a promotion.] My new go to! Need to be consistent with using. Yet to see any results on fine lines.
Date published: 2026-03-11
Rated 5 out of 5 by from Love it As always this brand never fails to deliver. Gorgeous Vitamin C, no nasty smell, absorbs quickly and provides amazing results. Another winner in my beauty regime arsenal.
Date published: 2026-03-10
Rated 5 out of 5 by from Works a treat [This review was collected as part of a promotion.] I use this every morning to help with over dry yet oily skin. Works a treat.
Date published: 2026-03-07
Rated 5 out of 5 by from Really lovely product, I’m enjoying Really lovely product, I’m enjoying the citrus smell when you apply it. My skin feels fuller and more ready to meet the winter weather.
Date published: 2026-03-03
Rated 5 out of 5 by from Love! Feel like this has made a really big difference to my complexion since I started using it! I love that they have the sample sizes available to purchase. I thought this was quite pricey at first but I’ve used it every day for 4 weeks and I’m only about halfway through, so it’s a really great value sample size to see if you like it and how it reacts to your skin.
Date published: 2026-02-26
Rated 2 out of 5 by from Greasy Too oily, doesn’t absorb greatly. My skin feels heavy and greasy after.
Date published: 2026-02-25
Rated 5 out of 5 by from Delicious for my skin Melts into the skin beautifully, disappearing quickly so the next serum and creams can be applied. Very happy with the results
Date published: 2026-02-22
Rated 5 out of 5 by from Radiance This product certainly has an immediate effect. It is wonderfully absorbent, smells delicious and makes the skin look radiant. Makeup also looks beautiful over it. The only slight negative in my case was to avoid applying it on the oiler part of my skin because I got some congestion with whiteheads and bumps.
Date published: 2026-02-20
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Can I use this serum under eyes?

Asked by: Anonymous
Yes absolutely! 
Answered by: Anonymous
Date published: 2023-05-24

What % vitamin c?

Asked by: Anonymous
The tetrahexyldecyl ascorbate (Vitamin C) in C-Tetra serum is 7%.
Answered by: Anonymous
Date published: 2023-05-24

What percentage of vitamin c does this contain?

Asked by: Anonymous
30%
Answered by: Anonymous
Date published: 2023-03-04
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