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
Nataliia Y. from
Lovely vitamin C serum
[This review was collected as part of a promotion.] One of my favourite Medik8 products. It feels lovely on the skin, absorbs well and gives my complexion a fresh, healthy glow. I also like that it doesn’t feel sticky or heavy.
Date published: 2026-09-06
Rated 5 out of
5
by
Jayne G. from
My go to serum
This is by far my favourite serum, and believe me, I’ve tried plenty! It does exactly what it says it’ll do and I love citrus scent. Brightens my skin and brightens my mind!
Date published: 2026-09-06
Rated 5 out of
5
by
Jude M. from
Love love love
[This review was collected as part of a promotion.] I am new to this skincare range and OMG this did not disappoint, I absolutely love this serum and gives my skin the nicest glass skin glow! Feels beautiful. My skin will thank me for this!
Date published: 2026-09-04
Rated 5 out of
5
by
Lynsey M. from
C-tetra
[This review was collected as part of a promotion.] Love this product it feels so enriching for my skin.
Date published: 2026-09-01
Rated 4 out of
5
by
Anna from
Good & Effective
[This review was collected as part of a promotion.] Good product and effective although will be looking o explore other vit c Medic8 products as consistence a bit oily. Overall does the job perfectly !
Date published: 2026-09-01
Rated 5 out of
5
by
Dawn H. from
Vit c serum
[This review was collected as part of a promotion.] Medik8 Vit c serum is quite possibly the best on the market. We all know the importance for using Vit c daily. The difference it makes to the skin is amazing.
Date published: 2026-08-31
Rated 5 out of
5
by
Claire H. from
A firm favourite
[This review was collected as part of a promotion.] I love this stuff, used consistently I can see a real improvement from this potent formula in the texture of my skin. I use it each morning under moisturiser, it is light but hydrating, it doesn’t make my skin at all oily.
Date published: 2026-08-31
Rated 5 out of
5
by
Shermane O. from
Best Vitamin C
[This review was collected as part of a promotion.] I’ve tried many different brands of vitamin C, but Medik8 C-Tetra has become one of my favourites. My skin feels softer and smoother, and I’ve noticed it looks brighter with a lovely healthy glow. It absorbs beautifully without feeling sticky or heavy, and a little goes a long way. I’m so pleased with it that I now have my husband using it too! Definitely one I’ll keep repurchasing.
Date published: 2026-08-31
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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