Looks like you're shopping from United States. Change your currency to USD.
Skip to main content


Simply select the currency you'd like to shop in below:


C-Tetra Liquid Vitamin C Antioxidant Serum by Medik8

30ml | SKU# MUK200028306
€ 49,00

This item is currently not available.

Add to cart options


Free UK Standard delivery

  • Select Size
Product Actions
Product added to bag

Please note we are unable to ship Medik8 products to Europe at this time.

Medik8's cult-favourite vitamin C serum featuring tetrahexyldecyl ascorbate, a gentle form of vitamin C. Perfect for those who are new to using vitamin C in their skincare routine.

Tetrahexyldecyl ascorbate is an oil soluble, 100% stable form of vitamin C which remains freshly potent from the very first use to final drop. A powerful antioxidant, it's protective qualities are reinforced with vitamin E. Combined, these actives help to tackle sun and pollution-induced damage.

C-Tetra minimises the appearance of all signs of skin ageing. The jojoba-based, lightweight formula with an uplifting citrus scent, absorbs rapidly to leave skin looking illuminated, refreshed and youthful.

Medik8 recommend a simple, highly effective anti-ageing strategy of using vitamin C and sunscreen in the morning and vitamin A at night. This strategy is called: CSA.

Key Benefits:
  • Contains tetrahexyldecyl ascorbate, a stable and gentle yet effective form of vitamin C
  • Enhances skin radiance
  • Antioxidant protection
  • Minimises the appearance of fine lines and wrinkles
  • Combats sun and pollution damage
How to Apply
After cleansing skin in the morning, apply 4 drops across the face, neck and décolletage. Leave to absorb before applying your moisturiser.

Free when you spend €50
Receive your order in 5-7 working days* (Please note, during Sale periods and promotional offers this may take up to 7 working days).

Delivered instantly by email, Free Delivery

If you'd like to send your order as a gift, we can add a beautiful finishing touch with our gift wrap. Choose complimentary gift wrap at checkout.

*This option is available for all UK Mainland addresses, excluding the Scottish Highlands and other parts of Scotland.

About Medik8
Achieve healthy, beautiful skin with Medik8. Now available at Space NK, its science-backed formulas are 100% vegan and cruelty-free.

Email me when available

Enter your email address to receive an alert when this is back in stock

Email me when available

Thanks! You will be notified.
Item has been added to your wish list!Visit >
What other customers think
C-Tetra Liquid Vitamin C Antioxidant Serum is rated 4.7 out of 5 by 41.
Rated 5 out of 5 by from Helped my skin a lot I started using this product after it was recommend to me by a facialist. I have dehydrated skin and had little dry spots/textured skin near my nose on my cheeks and this really helped clear up my skin and brighten it. It’s such an affordable price compared to other vitamin c which tend to be too oily but this just absorbs into the skin and love the skin behind the product and brand,
Date published: 2021-02-28
Rated 5 out of 5 by from Wish I found this earlier! I’ve been trying to follow the Medik8 CSA philosophy and since using this product, my skin has brightened. I’ve never been complimented on my skin before using this product. I definitely recommend embedding this into your routine. I also have some bad pigmentation from spot scaring and this is helping.
Date published: 2021-02-26
Rated 2 out of 5 by from Simply normal gentle serum This serum is very gentle and does not irritate my sensitive skin. It is slightly oily for me and takes a little longer to absorb than normal vitamin c serum although it is lightweight. Perhaps, I have just used it for a short period of time, I could hardly see any different. While Omorovicza daily vitamin c works a lot better and quickly brighten my complexion although it is a lot more expensive.
Date published: 2021-02-20
Rated 5 out of 5 by from Love it! Been using this amazing serum for 3 months. It has made such an improvement to the look and feel of my skin. It just sinks into the skin and smells amazing. It really makes my skin look even better when used with my moisturiser and under my makeup. I have no complaints and would definitely recommend and purchase again.
Date published: 2021-02-18
Rated 5 out of 5 by from Zesty, bright skin I bought this product a month ago based on reviews on here after reading up on skincare during lockdown and wanting to add Vitamin C to my skincare routine. I use this product in the morning after cleansing and it is light and is quickly absorbed by my skin. It smells amazing and I have noticed a big improvement in how bright and more even my skin tone is since using. It is also quite light and not too heavy like some vitamin C serums
Date published: 2021-02-17
  • y_2021, m_3, d_3, h_8
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.14
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_41
  • loc_en_GB, sid_MUK200028306, prod, sort_[SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_spacenk-en
  • bvseo_sdk, dw_cartridge, 17.1.0, p_sdk_3.2.0
  • CLOUD, getContent, 8ms
  • reviews, product
By entering your email you consent to the use by Space NK of your personal data in accordance with our T&Cs and Privacy Policy