Vitamin K + Retinal 1% Eye Cream

Niacinamide — Vitamin B3 — a broadly-tolerated all-rounder that strengthens the skin barrier, evens tone and helps regulate oil. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~5%. OTC cap 10%. Give it 8–12 weeks for tone. Suits all skin types. One of the best-tolerated actives there is — fine for every skin type, and especially handy for oil and uneven tone.

Retinol — A vitamin-A derivative that speeds cell turnover — the best-evidenced ingredient for fine lines and texture over months of nightly use. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~0.3%. OTC cap 1%. Give it 12 weeks minimum; best gains around 6 months. Best for Oily, Combination, Normal. Powerful but irritating early on. Oily and normal skin adapt fastest; dry and sensitive skin should start low and buffer with moisturiser.

Sodium Hyaluronate — A humectant that holds water in the upper skin — pure hydration, tolerated by essentially everyone, at any concentration. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~1%. Works Ongoing while you use it; no weeks-long build-up to wait for. Suits all skin types. Pure hydration — suits everyone, and dry or dehydrated skin most of all. Apply on damp skin and seal it in.

Caffeine — Constricts surface blood vessels, so it temporarily reduces under-eye puffiness. Honest limit: the effect is temporary, and the evidence on dark circles is modest — it won't erase pigment-based circles. The strength is not printed, so we cannot judge the dose; that counts against the brand. Works from ~3%. OTC cap 5%. Suits all skin types. A temporary de-puffer for the under-eye — low-risk for every skin type. Just don't expect it to erase pigment-based dark circles.

Niacinamide: a review on dermal delivery strategies and clinical evidence ›

Niacinamide - mechanisms of action and its topical use in dermatology ›

Mechanistic Basis and Clinical Evidence for the Applications of Nicotinamide (Niacinamide) to Control Skin Aging and Pigmentation ›