Redonyl® Ultra

Ron Hines DVM PhD

My March/April copy of Today’s Veterinary Practice arrived today. Browsing through it, I noticed a full-page ad for Dechra’s Redonyl® Ultra, a newly introduced product to “support skin mast cells”.It said that Redonyl® Ultra causes mast cells to release less histamine and other inflammatory compounds which would help reduce seasonal allergies. Skin “support” products come and go. What caught my eye was its 21 letter active ingredient, palmitoylethanolamide (PEA). I had never heard of this compound before.

Dechra is or was a UK-based company with a branch office in Overland Park, Kansas. Pharmaceutical companies change hands frequently swap patents frequently and sell the same product under multiple names or custom brand insignias. So you can never be sure. Two of Dechra’s well known veterinary products State-side are Vetoryl® (trilostane) for Cushing’s disease  and Felimazole® (methimazole) for hyperthyroid cats.

Dechra’s US site just promotes the product as “supporting skin health in seasonally allergic dogs”. Innovet Italia in Saccolongo, Italy holds the patents on Redonyl® Ultra and markets it there with a package of other skincare products. Their site is in Italian so I cannot navigate it. However various UK sites describe Redonyl® Ultra as “A complementary food with high quality nutrients to improve the function of the skin in cases of dermatoses (skin problems?) and excessive hair loss and that it contains a balance of ingredients that play an important role in the physiology of the intact kin barrier, a combination of palmitoylethanolamide (PEA), essential fatty acids and biotin to prevent or balance nutritional deficiencies and to help maintain healthy skin: essential fatty acids (GLA+EPA/DHA for vital barrier function and skin immune response. Biotin (vitamin H), important for the synthesis of fatty acids and maintain an optimal skin condition, PEA-UM (ultramicronized) to calm the skin and help maintain the physiological function of cutaneous mast cells.” (Homeovet International, etc.)

Itchy dogs and how best to treat them have vexed veterinarians since the 1920s when canines replaced horses as our primary source of income. The Wikipedia entry wasn’t particularly enlightening other than that I learned that PEA is an ammoniated     fatty acid that has been proposed to have anti-inflammatory and anti-pain (nociceptive) properties. Switching to PubMed, I found that there are 888 palmitoylethanolamide (PEA) study entries. The claimed benefits of PEA range from its success in treating Alzheimer’s disease, depression, brain fog, osteoarthritis of the knee, hardening of the arteries (atherosclerosis), inflammatory bowel disease, endometriosis, Parkinson’s disease, decreased vitality, inflammation and pain. Almost all these articles end by stating, “More studies are warranted for assessing the drug’s-related efficacy”. However none of those “further studies” are ever done. Another observation is that the vast majority of these positive articles are products of Italy. (read here)   Not a single article of the many I read found a disease for which PEA was not proposed as being beneficial. Truly a wonder drug. 

Your body and your pet’s body naturally synthesize PEA from palmitic fatty acid .  Palmitic acid makes up 21-30% of the body’s fat. (read here) Commercially PEA it is usually manufactured from palm oil. It also occurs in moderate amounts in egg yolks, peanuts, soybean products and various vegetable oils. PEA appears to have no detectable toxicity – even at high doses (1000 mg/kg/day orally for 90 days in rats. (read here)  PEA is readily available on and at nutrition stores.

A challenge in increasing body PEA level with oral supplements is that the compound barely dissolves in water (too lipophilic). To get around that, various methods are used to make the powdered PEA particles as small as possible (micronization). The smaller the particles, the more their surface area is exposed to gastrointestinal liquid and hence the better the absorption. (read here) One Italian study claimed that ultramicronized palmitoylethanolamide was beneficial to cats with flea allergies. (read here) Another claimed that it cured four lame horses. (read here)

Does Anyone In The United States Evaluate PEA-containing Products For The Health Claims Made Or For Effectiveness?


Medications to treat humans and pets are monitored by the FDA. But the FDA considers PEA to be a food not a medicine – no different that apples, milk or peanut butter. Consequently the FDA only monitors for dangerous contamination. The commonly used word for foods and dietary supplements that make veiled medical claims are nutraceuticals. To stay in the FDA’s good graces the manufacturers of these products do not claim outright that any of them are able to cure or lessen any specific disease. When the stray over that line, the FDA sends them a 483 warning letter. To avoid these letters the nutraceutical companies use the word “support” eg kidney support, liver support, brain support etc. That is because if they used the words treat, cure, improve, lessens the symptoms of, etc. they would have to prove to the FDA’s satisfaction that the products they sell actually do that. The patents listed in NAVC promo page ad are 6,548,550, 8,470,373 & 8,663,701. Patent 6548550 actually states that PEA ( N-palmitoylethanolamide aka palmidrol) is an effective adjunct treating eosinophilic granuloma in cats as well as the horse keloids I mentioned earlier. It suggests the option for the compound to be used topically, transdermally, micro-enemas, creams, ointments, sprays, gels and foams. US8,470,373 assigned to the Epitech Group, relates to their “ultra-micronization” process used to form their brand of PEA. US8663701B2/en also relates to their patent on the method that those PEA particles are made ultra-small <6 microns.

Is This Product Going To Benefit My Dog Or Cat?

I don’t know. If you give Redonyl® Ultra to your dog or cat and you see some improvement please let me know.  I’m sure many other pet owners would like to know. If it didn’t seem to help we would like to know that too. Send me an email and I will add your anonymous observations below.

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