A very underrated hydrating and soothing product is the Amino Acids + B5 serum from The Ordinary.
This serum has, as most of The Ordinary products, a very simple formula:
*17% combination of several Amino Acids found in skin's own Natural Moisturizing Factors to enhance barrier support and elasticity.
*B5 or Panthenol to provide hydration while assisting in barrier support and soothe skin.
*Water
*Free of fragrance, essential oils, gluten, parabens, Phenoxyethanol, silicones and drying alcohols.
This is a thin and liquid serum that has the same texture of a hydrating toner. There's no oil in the formula and absorbs inmediately.
It's colourless and almost odourless.
I use some drops right after my toner or even mixed in a serum or moisturizer.
I find it super hydrating and way more soothing than many other soothing serums in the market.
30 ml go for about 8€ (I buy at @deciem website) and I can only recommend you trying it.
