Allantoin is one of my favorite herb derived cosmetic ingredients. Its chemical name is 5-ureide-hydantoin. It is used in both cosmetics and drug preparations because of its ability to boost wound healing. Studies have found allantoin has wound healing, anti-irritating, hydrating, keratolytic, analgesic, cell proliferative and epithelial stimulating effects. Its beneficial effect on wound healing seems to primarily be inhibiting the inflammatory response. Allantoin enhances desquamation of dead upper layers of skin meaning that it promotes exfoliation and thus improves the smoothness of skin.
Allantoin is found in herbs including comfrey, plantain, yam, borage, tea, horse chestnut, uva ursi, and sour cherry stems. It is also found in animals (plants, animals and humans have very similar biochemistry. In fact, at one time blowfly larvae were used to treat severe wounds because of its high content of allantoin. Comfrey powder was used during WWI to treat wounds.
Allantoin is formed from uric acid which occurs from breakdown of purine. I love when my current reading takes me back to college biochem classes; ah, yes, purine salvage pathway. Purines include adenine and guanine which make up nucleic acids (DNA and RNA). The body is very conservative and purines from the breakdown of nucleic acids or foods are typically salvaged to be reused in new nucleotides. Just in case you are interested in purine metabolic pathways here is a short youtube video I found as a refresher: http://www.youtube.com/watch?v=mIJVb_HXUQk.
When purines do breakdown (instead of being salvaged) they form uric acid which in most organisms is converted to allantoin by the enzyme uricase. Humans however, do not have this enzyme and so do not make allantoin, or at least not significant amounts. Allantoin will however, accumulate in times of oxidative stress and is a marker for that. Perhaps the fact that humans do not have the uricase enzyme that breaks down uric acid is the reason humans get gout; a disease caused by accumulation of uric acid in the joints.
But back to allantoins role in skin care. Allantoin is a white, odorless powder that is safe and non-allergenic. Its properties make it appropriate for aging skin, acne skin, scars, psoriasis, eczema, diaper rash as well as just dry, chapped skin. Because its an anti-irritant it is also suitable for very sensitive skin. It is typically used at concentrations from 0.1% to 2% but sometimes higher for pharmaceutical preparations.
How does Colorado Aromatics use allantoin? In three of our balms we use allantoin containing herbs; comfrey in our Joint Jam for its analgesic effect, plantain in our Knuckle Balm for its wound healing effect and comfrey again in our Sole Pleasure foot butter for its softening and keratolytic effect. In our higher end products we use pure allantoin in our Springtide Antiaging Cream for its skin regeneration properties and antiaging properties and in our Oasis Spray Lotion for its anti-irritant properties. We also use it in our body powder to decrease itching and to sooth rashes.