HOT ! LEVEL 4 – pH OPTIMUM RETINOL RESTORING - 8000 IUs

Formulated For

Deep wrinkles, significant texture irregularity, advanced photoaging. Your skin has tolerated Level 3 and is ready for maximum-intensity dermal renovation. This is the concentration Dr. Koo uses for pre-surgical skin conditioning.

The Mechanism

At 8,000 IUs, Level 4 activates the full spectrum of nuclear receptor-mediated gene transcription — aggressive collagen induction, comprehensive MMP downregulation, and profound epidermal renewal. Histologically, this produces measurable Type I collagen increase and restoration of the dermal-epidermal junction (DEJ) undulation that flattens with age. Melanocyte activity is reduced, normalizing pigment distribution. The two-step enzymatic conversion (retinol to retinal to retinoic acid) still acts as a dose buffer — delivering prescription-level architectural remodeling with better tolerance than direct tretinoin.

Clinical Timeline

Weeks 16–32: profound dermal renovation, significant wrinkle reduction, restored firmness, normalized pigmentation. Extended adjustment period of 3–6 weeks. This level delivers the most dramatic visible transformation in the system.

How To Use

Apply nightly to clean skin. The adjustment period is longer at this concentration — your skin is undergoing comprehensive architectural remodeling. Pair with THD-Ascorbate Vitamin C Serum for structural collagen stabilization and broad-spectrum SPF 30+ daily. If you experience persistent sensitivity beyond 6 weeks, step back to Level 3.

Ingredients

Purified Water, Niacinamide, Squalane, Glycerin, Glyceryl Stearate, PEG-100 Stearate, Caprylic/Capric Triglyceride, Cetyl Alcohol, Sclerocarya Birrea Seed Oil, Cocos Nucifera (Coconut) Oil, Hexylresorcinol, Retinol, Ceramide NP, Sodium Hyaluronate, Phytosterols, Aloe Barbadensis Leaf Extract, Bisabolol, Dimethicone, Tocopheryl Acetate, Persea Gratissima (Avocado) Oil, Ethyl Linoleate, Mica, Olea Europaea (Olive) Fruit Oil, Zingiber Officinale (Ginger) Root Extract, Cetearyl Alcohol, Disodium EDTA, Phenoxyethanol, Sodium Polyacrylate, Polysorbate 20, Ethylhexylglycerin, Stearic Acid