{"product_id":"principia-rn-03-retinol-serum","title":"Principia RN-0.3 Retinol Serum 0.3% + Vitamin E 0.5% for Fine Line \u0026 Firmness Care, 1.01 fl oz (30 mL)","description":"\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003e\u003cstrong\u003ePrincipia RN-0.3 \u003c\/strong\u003eis a Brazilian dermocosmetics night serum designed for a refined, results-focused routine—supporting the look of smoother texture, improved radiance, and visibly softened fine lines over time. With \u003cspan class=\"font-semibold\"\u003e0.3% retinol\u003c\/span\u003e paired with \u003cspan class=\"font-semibold\"\u003e0.5% vitamin E\u003c\/span\u003e, it brings an elegant balance of renewal and antioxidant support, making it a strong fit for customers who want a high-performance anti-aging step that still feels modern, minimal, and easy to integrate.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003eThis serum is ideal for international customers, salon retail shelves, and resellers seeking a globally recognized active with clear concentration and a straightforward, professional story.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch3\u003eKey Benefits\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003eFine line appearance care\u003c\/strong\u003e:\u003c\/span\u003e Helps soften the look of fine lines and expression lines with consistent use.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003eFirmness + elasticity appearance\u003c\/strong\u003e:\u003c\/span\u003e Helps improve the look of firmness and elasticity over time.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eRadiance support:\u003c\/span\u003e\u003c\/strong\u003e Helps enhance the look of glow for a fresher, more luminous finish.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003eTexture refinement\u003c\/strong\u003e:\u003c\/span\u003e Helps improve the look of uneven texture for a smoother surface appearance.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eTone uniformity support:\u003c\/span\u003e\u003c\/strong\u003e Helps refine the look of uneven tone and discoloration.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003ePore appearance support\u003c\/strong\u003e:\u003c\/span\u003e Helps reduce the look of enlarged pores as texture looks more refined.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003eDermatologically tested (brand-reported)\u003c\/strong\u003e:\u003c\/span\u003e The brand reports irritation and sensitization testing, plus hypoallergenic \/ non-photoirritating evaluation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003e\u003cspan class=\"font-semibold\"\u003eHow to use\u003c\/span\u003e\u003c\/h4\u003e\n\u003cp\u003eUse daily, only at night. Apply on clean, dry skin before creams. Dispense a few drops onto fingertips (avoid touching the dropper to skin) and spread gently over the face, \u003cspan class=\"font-semibold\"\u003eexcluding the eye area\u003c\/span\u003e.\u003cbr\u003eDuring the first week, use small amounts on alternate nights. Wear broad-spectrum sunscreen daily and avoid sun exposure without protection.\u003c\/p\u003e\n\u003cp\u003eIn a \u003cspan class=\"font-semibold\"\u003e60-day perceived efficacy study\u003c\/span\u003e, participants reported improvements in: \u003cspan class=\"font-semibold\"\u003eglow (100%)\u003c\/span\u003e, \u003cspan class=\"font-semibold\"\u003efine lines (97%)\u003c\/span\u003e, \u003cspan class=\"font-semibold\"\u003ewrinkles appearance (97%)\u003c\/span\u003e, \u003cspan class=\"font-semibold\"\u003etexture (97%)\u003c\/span\u003e, \u003cspan class=\"font-semibold\"\u003etone (97%)\u003c\/span\u003e, \u003cspan class=\"font-semibold\"\u003efirmness (87%)\u003c\/span\u003e, and \u003cspan class=\"font-semibold\"\u003eelasticity (87%)\u003c\/span\u003e. The brand also reports instrumental measurements showing variation in firmness and elasticity parameters over 60 days, plus comedogenicity\/acnegenicity evaluation. Results may vary.\u003c\/p\u003e\n\u003ch3\u003eIngredients Highlights\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003eRetinol (0.3%)\u003c\/strong\u003e:\u003c\/span\u003e A vitamin A derivative whose molecules can penetrate deeper layers of the skin. Retinol is widely used to support antioxidant activity and to promote collagen- and elastin-related pathways that help improve the look of fine lines, firmness, elasticity, and radiance. It also supports surface renewal, helping refine the look of texture and uneven tone over time.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003e\n\u003cspan class=\"font-semibold\"\u003e\u003cstrong\u003eVitamin E (0.5%)\u003c\/strong\u003e:\u003c\/span\u003e An antioxidant naturally found in foods like nuts, spinach, and olive oil. In skincare, vitamin E helps neutralize free radicals and is associated with photoprotective support, helping reduce the visible effects of sun-related stress when paired with daily sunscreen.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003ch4\u003eAllergen warnings \/ cautions\u003c\/h4\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cul class=\"ml-1 list-outside list-disc\"\u003e\n\u003cli class=\"py-0\"\u003eFor external use only. Do not apply on irritated, broken, or compromised skin.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003eAvoid contact with eyes; do not apply in the eye area. If contact occurs, rinse thoroughly.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003eRetinol may cause temporary dryness, redness, or peeling; start slowly (alternate nights for the first week).\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003eUse broad-spectrum sunscreen daily and avoid sun exposure without protection.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003eIf pregnant or breastfeeding, consult a physician before use.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003eKeep out of reach of children. Do not use on children.\u003c\/li\u003e\n\u003cli class=\"py-0\"\u003eAccording to the brand, the formula is free from parabens, petrolatum, sulfates, silicones, fragrance, dyes, and gluten.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003ePrincipia\u003c\/span\u003e \u003c\/strong\u003eis a Brazilian \u003cstrong\u003edermocosmetics \u003c\/strong\u003ebrand founded in 2020 in São Paulo with a clear mission: \u003cspan class=\"font-semibold\"\u003edemocratize high-performance \u003cstrong\u003eskincare\u003c\/strong\u003e\u003c\/span\u003e\u003cstrong\u003e \u003c\/strong\u003ethrough science-backed formulas, radical ingredient transparency, and fair, accessible positioning. Instead of relying on hype, Principia focuses on what matters most for results-driven routines—\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eactive ingredients at disclosed percentages\u003c\/span\u003e, straightforward formulations, and a minimalist, clinical aesthetic designed for everyday use.\u003c\/strong\u003e\u003c\/p\u003e\n\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eWhen should I use Principia RN-0.3?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eUse it at night only, on clean, dry skin, before moisturizer. Always wear sunscreen during the day.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eHow do I introduce retinol if I’m new to it?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eStart with small amounts on alternate nights for the first week, then increase to nightly use as tolerated.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eCan I apply this retinol serum around my eyes?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eNo. The brand advises avoiding the eye area.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eCan I use RN-0.3 with other active ingredients?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eMany routines combine actives, but to reduce irritation, avoid layering multiple strong exfoliants in the same night. Consider alternating nights when using acids.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan class=\"font-semibold\"\u003eIs Principia cruelty-free?\u003c\/span\u003e\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe brand states it does not test on animals.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"size-full [\u0026amp;\u0026gt;*:first-child]:mt-0 [\u0026amp;\u0026gt;*:last-child]:mb-0 space-y-2\"\u003e\n\u003cp\u003eComplete your routine by exploring \u003cspan class=\"text-gray-500\" title=\"Blocked URL: {{INTERNAL_LINK}}\"\u003eour curated \u003ca href=\"https:\/\/mkpbr.com\/collections\/principia\"\u003ePrincipia Collection\u003c\/a\u003e\u003c\/span\u003e for a clean, balanced, everyday glow.\u003c\/p\u003e\n\u003ch3\u003eAdd Principia RN-0.3 to your cart and elevate your night routine with Brazilian dermocosmetic precision.\u003c\/h3\u003e\n\n\n\u003c\/div\u003e\n\u003cdiv style=\"margin-top: 18px; background: #F6F7FB; border: 1px solid #E7E9F3; border-radius: 14px; padding: 12px; color: rgba(20,32,62,.74); font-size: 12.5px; line-height: 1.6; max-width: 100%; box-sizing: border-box; overflow: hidden;\"\u003e\n\u003cstrong style=\"color: #14203e;\"\u003eDisclaimer:\u003c\/strong\u003e For external use only. Patch test before use and discontinue use if irritation occurs. Individual results may vary. Product packaging may be labeled in Portuguese. Our Brazilian-brand products are sourced in Brazil and are regularized with ANVISA (Agência Nacional de Vigilância Sanitária), Brazil's national health authority, under the applicable regulatory framework for each product category. ANVISA regularization applies to the Brazilian market and is not equivalent to U.S. FDA approval. See our full \u003ca href=\"\/en-ie\/pages\/disclaimers\" style=\"color: rgba(20,32,62,.74); text-decoration: underline;\"\u003eDisclaimers \u0026amp; Important Information\u003c\/a\u003e.\u003c\/div\u003e","brand":"Principia","offers":[{"title":"Default Title","offer_id":52626387042620,"sku":"MKPBR2024-1974","price":41.24,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0090\/2840\/3278\/files\/principia-rn-0-3-retinol-serum-0-3-percent-vitamin-e-0-5-percent-1-01-fl-oz-30-ml-front-bottle-buy-now-at-mkpbr-com-worldwide-shipping_d4e6d701-85aa-476c-adec-9ac1d721d8fd.png?v=1784527722","url":"https:\/\/mkpbr.com\/en-ie\/products\/principia-rn-03-retinol-serum","provider":"MKPBR - Shine Like a Brazilian","version":"1.0","type":"link"}