Hyalu B5 Pure Hyaluronic Acid Serum — Reddit Reviews
Updated October 14, 2026
Hyaluronic acid serum for deep damp-skin hydration; thick, fragranced, and irritating for some.
What the community says
A layered hyaluronic acid serum with glycerin, panthenol, and madecassoside, best applied to damp skin beneath moisturizer for dehydrated or tret-dried faces. Alcohol denat and parfum make it a risky pick for rosacea, reactive skin, or anyone prone to stinging.
What this means for you
What people love
Watch out for
Product details
Use caution
Skin Type
Product Traits
Key Ingredients
Where to buy
What the science says vs. what Reddit says
Dehydration
Not proven yet
Few or mixed studies. This claim isn't established.
Panthenol: 2 studies tested it on its own. See all 3 studies
On Reddit: After DeepFrac laser treatment, one user credits it with saving their skin. 17 mentions
Skin Barrier
Not proven yet
Few or mixed studies. This claim isn't established.
Panthenol: 1 study tested it on its own. See all 10 studies
Research context, not treatment advice. Studies are about the ingredient, not necessarily this exact product.
Real Reddit threads — 67 mentions across 17 threads
La Roche-Posay Hyalu B5 Pure Hyaluronic Acid Serum on Reddit, in one place — 17 threads from r/tretinoin, r/koreanskincare and 4 more, summarized.
“Serum: La Roche-Posay Hyalu B5 Serum with Hyaluronic Acid”
Positive
“I have learned that hydration is key to make your skin happy, especially when on something as drying and irritating as tretinoin.”
Positive
“Serum: La Roche-Posay Hyalu B5 Serum with Hyaluronic Acid.”
Positive
“Morning: - La Roche Posay Hyalu B5 serum (this product makes a huge difference for me for deep hydration) straight on wet skin”
Positive
“La Roche Posay Hyalu B5 serum”
Positive
“this product makes a huge difference for me for deep hydration”
Positive
“La Roche Posay Hyalu B5 Eyes completely got rid of my very bad under eye bags.”
Positive
“Couldn’t recommend LRP enough.”
Positive
“it didn’t impact the colour of my under eyes but got rid of the actual puffiness”
Positive
“Apply La Roche-Posay Hyalu B5 serum.”
Positive
“Non-tretinoin nights:”
Positive
“followed by Avène cleanser.”
Positive
“kept the rest of my routine super boring to isolate the results: thayers toner, beauty of joseon ginseng essence, lrp hyalu b5”
Positive
“and then a layer of the pink cream over the patchy areas.”
Positive
“That evening, everything I put on my skin seemed to sting, from the Cerave Hydrating cleanser to the la Roche Posay Hyalu B5 serum...”
Mentioned
“...everything I put on my skin seemed to sting...”
Mentioned
“...the la Roche Posay Hyalu B5 serum and even my beloved Aestura Atobarrier 360.”
Mentioned
