The Ordinary Azelaic Acid Suspension 10% Versus Paula's Choice C15 Super Booster

The Ordinary Azelaic Acid Suspension 10% Versus Paula's Choice C15 Super Booster Detailed comparison of The Ordinary Azelaic Acid Suspension 10% versus Paula's Choice C15 Super Booster. This calming serum is formulated around Azelaic Acid to calm redness and refine skin texture. This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. Water Isodecyl Neopentanoate Dimethicone Azelaic Acid Dimethicone/Bis-Isobutyl PPG-20 Crosspolymer Dimethyl Isosorbide Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer Polysilicone-11 Isohexadecane Tocopherol Trisodium Ethylenediamine Disuccinate Isoceteth-20 Polysorbate 60 Triethanolamine Ethoxydiglycol Phenoxyethanol Chlorphenesin Water, Isodecyl Neopentanoate, Dimethicone, Azelaic Acid, Dimethicone/Bis-Isobutyl PPG-20 Crosspolymer, Dimethyl Isosorbide, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Polysilicone-11, Isohexadecane, Tocopherol, Trisodium Ethylenediamine Disuccinate, Isoceteth-20, Polysorbate 60, Triethanolamine, Ethoxydiglycol, Phenoxyethanol, Chlorphenesin Ascorbic Acid Dipropylene Glycol Propanediol Glycerin Sodium Hydroxide PPG-26-Buteth-26 PEG-40 Hydrogenated Castor Oil Bisabolol Ferulic Acid Sodium Phytate Decylene Glycol 1,2-Hexanediol Sphingomonas Ferment Extract Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers. In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA. It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper. The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it interacting gently with the lipids and water in your outermost layer of skin. Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product). Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare. Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye. Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!). It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome. On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive. Another perk of this ingredient is that it stays functional across a wide pH range (3-10). You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own. Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU. Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages. Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon. Tocopherol is a fat-soluble antioxidant known as Vitamin E. You'll find th