Medik8C-Tetra
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
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\nIngredients
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.
See more...
Rated 5 out of
5
by
Susan C. from
Favourite Vit C
[This review was collected as part of a promotion.] I use this every day in the morning, and it does not cause any sensitivity issues. My skin looks so much brighter and radiant since using this. I have tried other brands of Vit C in the past, but have not looked back since using Medik8.
Date published: 2026-06-19
Rated 5 out of
5
by
Ross G. from
The best vitamin C ever
[This review was collected as part of a promotion.] This has to be my holy grail vitamin C. Although it is oil based, it isn’t oily. It sinks right in, leaves my skin feeling feather soft and provides an immediate glow. I’ve been using this for about 6 weeks now and people have commented on how nice my skin looks.
Date published: 2026-06-18
Rated 5 out of
5
by
Elena K. from
Pleasant to use and it
Pleasant to use and it helps even out skin tone well. However, the oil is extremely runny and pours from the dropper like water, making it difficult to control the amount. Honestly, it feels as though the dropper was designed this way so that the product gets used up faster and needs to be repurchased more often.
Date published: 2026-06-18
Rated 4 out of
5
by
Patricia M. from
Good product
[This review was collected as part of a promotion.] A good start in your vit c journey, i used 2 bottles of it. It has a good texture and your skin absorbs it well without feeling tacky. Hoever, I have now become obsessed with the 20% serum with exossomes.
Date published: 2026-06-17
Rated 5 out of
5
by
Aisha from
The best vitamin C serum i’ve used. Definitely worth the price and it lasts a long time as you only need a little. Has a beautiful orange smell to it aswell. I’ve been using for the best couple months and have seen improvement in my skins brightness
Date published: 2026-06-16
Rated 5 out of
5
by
Rian B. from
Love using this vitamin C
[This review was collected as part of a promotion.] This is always a staple in my routine. I have sensitive skin, and I’ve never had issues when using this. Always a repeat purchase.
Date published: 2026-06-14
Rated 5 out of
5
by
Caroline G. from
The best vitamin C I’ve
[This review was collected as part of a promotion.] The best vitamin C I’ve ever tried, my skin feels hydrated and it helps with uneven skin tone.
Date published: 2026-06-13
Rated 1 out of
5
by
Robyn d. from
Oily not much difference
[This review was collected as part of a promotion.] Akin just feel oily from products not hydrating and plump
Date published: 2026-06-12
Can I use this serum under eyes?
Yes absolutely!
Date published: 2023-05-24
What % vitamin c?
The tetrahexyldecyl ascorbate (Vitamin C) in C-Tetra serum is 7%.
Date published: 2023-05-24
What percentage of vitamin c does this contain?
30%
Date published: 2023-03-04
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