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C-Tetra

Medik8 C-Tetra 30ml

%0 4.75 | 1079 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 Amazing product! [This review was collected as part of a promotion.] Was recommended this product by my beatuy lady and I must say she was right it’s an amazing product it’s not heavy on my face and doesn’t leave it sticky like some other products do ! Would highly recommend it !!
Date published: 2026-10-14
Rated 5 out of 5 by from Vitamin C [This review was collected as part of a promotion.] Fantastic product! My skin looks luminous and healthy
Date published: 2026-10-12
Rated 5 out of 5 by from Lovely glow for no make-up days [This review was collected as part of a promotion.] I use this one alternately with the C-Tetra Advanced as part as my morning skincare routine. I find the C-Tetra does take that tiny bit longer to absorb into the skin vs. the C-Tetra Advanced given the oil texture, however it gives more of an immediate glow to the skin. I use this on no make-up days underneath my sunscreen!
Date published: 2026-10-10
Rated 5 out of 5 by from Tetra C [This review was collected as part of a promotion.] Never without this product- it has has been part of my routine for years - for me I use it to enhance the effects of my SPF
Date published: 2026-10-02
Rated 5 out of 5 by from Great! Great vitamin C serum! I use this in the morning after cleansing.
Date published: 2026-09-30
Rated 5 out of 5 by from Special glow [This review was collected as part of a promotion.] This makes my skin look amazing and I get compliments about looking fresh and bright.
Date published: 2026-09-29
Rated 5 out of 5 by from Amazing [This review was collected as part of a promotion.] I love this product! Makes such a difference to how my face feels & looks!
Date published: 2026-09-28
Rated 5 out of 5 by from Nourishes my skin [This review was collected as part of a promotion.] Love this. Wouldn’t be without it. Nourishes my skin before moisturising. Feels wonderful on.
Date published: 2026-09-28
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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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