The ABC Kit

The CSA philosophy, boxed

Vitamin C and sunscreen by day, vitamin A by night is the philosophy Medik8 built its name on, and this kit is that philosophy in miniature: C-Tetra's lipid-soluble vitamin C takes the morning, Retinol 3TR's 0.3% retinol takes the night, and Hydr8 B5 bridges both with panthenol and hyaluronic acid.

The four steps

Gentle Cleanse opens both ends of the day with a soft, rosemary-scented foam that respects the barrier. B5 hydration layers under everything. C-Tetra brightens and defends through the day; the retinol works the night shift, phased in gradually.

Why start here

0.3% is the classic retinol entry strength, and C-Tetra's tetrahexyldecyl ascorbate is vitamin C without the sting of the pure acid, which makes this the rare starter set that is a genuinely complete routine, SPF aside.

First-time active users who would rather have the routine decided for them; anyone returning to retinol after a break; and skin that has been circling medical-grade skincare and wants the whole argument in one box.

Worth knowing

Contains retinol: phase it in as directed, wear SPF daily, and set the kit aside if pregnant or breastfeeding. C-Tetra and the cleanser carry citrus and rosemary oils, with fragrance allergens on the label.

Morning and evening, cleanse with Gentle Cleanse, then press in six drops of Hydr8 B5. Mornings, follow with four drops of C-Tetra and finish with SPF.

Evenings, replace C-Tetra with Retinol 3TR: twice a week for the first fortnight, every other night for the next, then nightly as skin allows.

Use alongside

A complete routine bar two things: SPF every morning, and a moisturiser if your skin wants more cushion than the B5 gives. When the Retinol 3TR runs out, Crystal Retinal is the natural graduation.