This is an over the counter product - it does not require prescription.
Denosyl, a nutritional supplement, is the pure and stabilized salt of S-Adenosylmethionine for veterinary use only. It is the only brand researched in U.S. trials for veterinary use in dogs and cats. Denosyl is available in three strengths: as an enteric-coated 90 mg, 225 mg, and 425 mg tablet of active S-Adenosylmethionine. Because S-Adenosylmethionine is extremely sensitive to moisture, tablets are individually sealed in specialized moisture-resistant blister packs.