SAMe
What is SAMe?
SAMe (S-adenosylmethionine) is the bioactive form of methionine, an essential amino acid (building block of protein) abundant in foods, but especially concentrated in meat and sunflower seeds. Supplementation with methionine alone, however, does not necessarily markedly raise the level of bioactive methionine, or SAMe.
SAMe is one of the most commonly used supplements in human and animal medicine, and with good reason. It is involved in over 40 key chemical reactions in the body. This is because SAMe contains both sulphur and methyl groups. Methylation reactions in the body are necessary for the formation of adequate levels of brain chemicals called neurotransmitters. SAMe helps synthesize all neurotransmitters related to catecholamines, including epinephrine and dopamine. Epinephrine and dopamine deficiencies lead to depression and Parkinson's disease.
SAMe has shown significant promise in treating these disorders in clinical trials in humans, as well as other cerebral disorders including autism, peripheral neuropathy, spinal cord degeneration and Alzheimer's disease.
The sulphur groups of SAMe are likewise metabolically important. Glutathione, a key detoxifier and antioxidant in the body, is made from SAMe. SAMe itself also functions as an antioxidant. As such, it is helpful in protecting the liver. These antioxidant and detoxifying properties result in SAMe being able to reduce liver damage such as cirrhosis.
SAMe has several other effects in the body. It plays a key role in the breakdown of estrogen; the synthesis of carnitine (important for adequate heart function); the synthesis of choline (important for cognition and brain function); the synthesis of melatonin, allowing sleep; the synthesis of nucleic acids so that cells can divide; the degradation of histamine (reduces inflammation); and the synthesis of collagen.
"...commonly used in osteoarthritis."
SAMe is also an analgesic (pain reliever), and this together with its ability to promote collagen and cartilage synthesis and its anti-inflammatory properties results in it being commonly used in osteoarthritis. The efficacy of SAMe in relieving arthritic pain has approached that of many NSAIDs in clinical trials.
Why recommend administration of SAMe to my pet?
SAMe is widely prescribed for the same purposes in animals as it is in people. That is, SAMe is used for the treatment of canine cognitive disorders, suspected depression, osteoarthritis, and hepatitis. It should probably also be considered for the treatment of various neurological disorders, including degenerative myelopathy. It is appropriate for all species, since it is naturally present in all mammals. It is probably most commonly used in dogs, given their susceptibility to liver and musculoskeletal disorders.
How safe is SAMe?
SAMe is of great interest in the treatment of osteoarthritis, because it not only reduces inflammation and pain but also helps regenerate joint tissue.
"...extremely low toxicity..."
This, together with its extremely low toxicity, makes it probably one of the first treatments that should be considered for the treatment of arthritic dogs and cats. Side effects of SAMe are rare, and limited to mild nausea and gastrointestinal irritation. SAMe should also be used with caution in hyperexcitable animals, since it may heighten their mood further.
Where do I obtain SAMe and do I need a prescription?
Pet owners are cautioned against buying supplements without knowledge of the manufacturer, as supplements are not highly regulated and some supplements may not contain the labelled amount of ingredients. A prescription is not needed for SAMe. Your veterinarian may have preferred brands or sources of supplements that he or she will recommend.
© Copyright 2025 LifeLearn Inc. Used and/or modified with permission under license. This content written by LifeLearn Animal Health (LifeLearn Inc.) is licensed to this practice for the personal use of our clients. Any copying, printing or further distribution is prohibited without the express written consent of LifeLearn. This content does not contain all available information for any referenced medications and has not been reviewed by the FDA Center for Veterinary Medicine, or Health Canada Veterinary Drugs Directorate. This content may help answer commonly asked questions, but is not a substitute for medical advice, or a proper consultation and/or clinical examination of your pet by a veterinarian. Please contact your veterinarian if you have any questions or concerns about your pet’s health. Last updated on Nov 30, 2018.