Provitamin B5: a humectant that helps skin hold water and recover from irritation. Very well tolerated, with small but consistent studies.
Panthenol is converted in skin to pantothenic acid (vitamin B5), part of coenzyme A, which cells use to make barrier lipids. It is also a humectant in its own right, penetrates skin well and very rarely irritates. Dexpanthenol is its active form; 'vitamin B5' on a lotion label usually means panthenol.
You'll find it in body lotions, lip and nappy balms, after-sun and hair products, typically at 0.5-5%.
Small controlled studies show dexpanthenol creams speed barrier recovery after irritation, increase hydration and reduce redness compared with the same cream without it. Reviews also report benefits for minor wounds and irritated skin, though much of the research is linked to makers of dexpanthenol products.
Reviews topical dexpanthenol: it improves stratum corneum hydration, reduces water loss, speeds epidermal regeneration in wounds and eases irritation symptoms, with minimal risk of irritation or sensitization.
After detergent (SLS) irritation, a dexpanthenol cream sped barrier repair and increased hydration more than its vehicle, and reduced redness, which the vehicle did not.