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C-Tetra

Medik8 C-Tetra 30ml

%0 4.75 | 1052 reviews
Box

£45.00 (£1.50 per ml)

Free UK delivery

In stock

This product is temporarily out of stock

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

Product Description

Restore the look of skin radiance in just 7 days* with cult-favourite C-Tetra.

Formulated with a stabilised form of vitamin C (7%) called tetrahexyldecyl ascorbate (pronounced 'tetra-hexul-deckul as-CORR-bate'), this lightweight serum works to visibly brighten uneven skin tone and reduce the look of fine lines and wrinkles, while remaining gentle on sensitive skin.

Fortified with vitamin E, this antioxidant powerhouse also protects the skin against the ageing and damaging effects of free radicals for a more youthful and healthy-looking complexion overall. The perfect option for those who are new to vitamin C, or those with 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.

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.

HOW TO USE
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.

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.

More information

*Product packaging may vary by region\n\n

Ingredients

Simmondsia Chinensis (Jojoba) Seed Oil, Cyclopentasiloxane, Cyclohexasiloxane, Tetrahexyldecyl Ascorbate, Citrus Grandis (Grapefruit) Peel Oil, Tocopheryl Acetate, Limonene, PPG-12/SMDI Copolymer, 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 Review I’ve been using C-Tetra [This review was collected as part of a promotion.] Review I’ve been using C-Tetra and I’m really impressed with it. My skin feels noticeably smoother, more hydrated and has a lovely healthy glow. It gives my skin that fresh, plump. After using it consistently, my skin just looks healthier and more radiant. Definitely one of my favourite Medik8 products and one I would happily repurchase.
Date published: 2026-08-24
Rated 5 out of 5 by from Love Love Love this Vit [This review was collected as part of a promotion.] Love Love Love this Vit c serum its my fav thing to put on my face after cleansing. It feels lovely and smells amazing!
Date published: 2026-08-21
Rated 5 out of 5 by from LOVE this product! Doesn’t leave [This review was collected as part of a promotion.] LOVE this product! Doesn’t leave me oily and has helped with brightening my overall skin tone.
Date published: 2026-08-19
Rated 5 out of 5 by from Sleep in a bottle [This review was collected as part of a promotion.] Sinks right in. Smells so fresh and leaves me looking like I’ve had 8 hours sleep!
Date published: 2026-08-08
Rated 5 out of 5 by from If you have sensitive skin swich from treta c advance 20% to 7% [This review was collected as part of a promotion.] I devleloped skin reaction and my face looked darker when use 20% tetra advance so switched to 7% was the best decision
Date published: 2026-08-08
Rated 5 out of 5 by from Brilliant [This review was collected as part of a promotion.] This out of all the top products medik8 do is probably my favourite. . so easy and smooth too apply smells great and you just feel like it's so good for your skin.
Date published: 2026-08-07
Rated 5 out of 5 by from Even skin tone [This review was collected as part of a promotion.] Great product that helps to even my skin, I have been using it for many years now , definitely recommend.
Date published: 2026-08-04
Rated 5 out of 5 by from My skin loves it [This review was collected as part of a promotion.] This vitamin C oil is just gorgeous. I tried a vitamin C cream from another brand which was recommended by a friend, however, it turned my nails orange and put me off using Vitamin C products. But I have recently changed most of products to Medik8 and though I would try this C Tetra as it was clear. It soaks in beautifully, my skin looks really good, I am in my late 50s and got told recently I don't look it. My make up goes on better. Will buy again. Oh and no orange nails yay
Date published: 2026-07-31
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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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