Dietary Supplements for Pets – Are They Drugs?

There is some confusing discussion in the public literature about how the FDA’s Center for Veterinary Medicine (FDA-CVM) regulates animal supplements. A recent article by Dr. L. Phillips Brown[1] and excerpted by J. Taylor[2] mentions that “FDA-CVM accepts the marketing of oral supplements for animals provided there is a recognized benefit, purpose or utility and they are not a substitute for a complete and balanced diet or represented to prevent or cure disease.” This statement suggests that oral supplements for animals, like dietary supplements for humans, are regulated under the Dietary Supplement Health Education Act (DSHEA). This rationale should not be used for marketing supplements for animals. The FDA-CVM’s assessment of DSHEA is that it was not intended for and does not apply to animals.[3] A notice for this policy was published in the Federal Register on April 22, 1996.[4] Nevertheless, the FDA-CVM has stated that it “does not object to the OTC marketing of dietary supplements in tablet, capsule, powder or liquid form for companion animals, similar to the special dietary preparations that are sold for humans” (FDA Compliance Policy Guide Section 690.100).[5] FDA-CVM has been clear in stating that the term “dietary supplement” in this sense only pertains to nutrients, which would include vitamins, minerals, protein supplements and fatty acid sources. The other types of supplements FDA-CVM recognizes (animal health supplements) are considered different from nutritional supplements and are regulated as drugs by FDA-CVM. Because FDA-CVM does not recognize DSHEA, many substances that are legally marketed in human dietary supplements would fall under the drug category for use in pets.

Under current law, nutritional supplements are considered foods and should achieve either Generally Recognized as Safe (GRAS) or food additive status. FDA-CVM will not generally object to the marketing of nutritional supplements for oral administration to companion animals provided that “there is a known need for each nutrient ingredient represented to be in the product for each animal for which the product is intended, the label represents the product for use only in supplementation of and not as a substitute for good daily rations, the product provides a meaningful but not excessive amount of each of the nutrients it is represented to contain, the labeling should bear no disease prevention or therapeutic (including growth promotional) representations…and should not be false or misleading” … and “the product is neither over-potent nor under-potent nor otherwise formulated so as to pose a hazard to the health of the target animal.”[6]

Meeting these requirements has been particularly onerous for dietary supplement manufacturers because the nutritional needs of companion animals have not been fully characterized and the process by which a nutritional need could be established could be very expensive and time consuming.[7]  The National Academy of Sciences-National Research Council publications Nutrient Requirements of Dogs and Cats,[8] Nutrient Requirements of Horses,[9] and the Official Publication of the Association of American Feed Control Officials Incorporated (AAFCO)[10] may be utilized to determine if a potential ingredient could qualify as a nutrient supplement. If an ingredient is not found in these references, in all likelihood the FDA-CVM will consider the dietary supplement to be an animal health supplement (i.e. drug) rather than a nutritional supplement. Animal health supplements require submission of a New Animal Drug Application (NADA) that demonstrates efficacy as well as safety. FDA-CVM will consider animal health supplements that have not been approved by this process as unapproved new drugs and will take appropriate corrective action.

The National Animal Supplement Council (NASC)[11] has pointed out that submission of NADAs for animal dietary supplements is problematic because “the courts have held that natural substances cannot be protected via intellectual property (patents).”[12] While it is true that NADAs require information about production methods and specifications, proprietary information can be marked as confidential and will not be available for dissemination to the public through the Freedom of Information Act (FOIA).  Therefore, product information that is not proprietary will be available for FDA-CVM NADAs by FOIA and should not be substantially different from information available on FDA-CVM GRAS dossiers through website access. Based on the current regulations it is clear that dietary supplements for pets that do not fit the definition of a nutritional supplement must be regulated as drugs. The requirement that efficacy and safety must be determined for animal health supplements may actually help manufacturers in the long run because efficacy must be demonstrated to substantiate any claims the company may want to make on the ingredient.

FDA-CVM is applying the definition of a drug in Section 210(g)(B and C) of the Federal, Food Drug and Cosmetic Act to oral supplements for animals, which states that the term “drug” includes “articles intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in man or other animals” and “articles (other than food) intended to affect the structure or any function of the body or man or other animals.” Therefore a structure/function claim that may be permitted for human dietary supplements under DSHEA may be considered a drug claim by FDA-CVM. When a substance, including one considered food, is intended to be used for treatment or prevention of disease or “non-food” structure/function effect, the FDA-CVM will likely consider the supplement to be a drug.[13] To ensure compliance with current regulations, claims for animal nutritional supplements should be based on nutritive value. Examples of compliant nutrient value claims include “calcium for proper bone structure” and “taurine for healthy heart function in cats.” Claims that are not based on nutritive value will most likely be considered health claims that must authorized by FDA-CVM.[14] One gray area is claims that are based on the ability of a supplement to increase growth promotion or increase feed efficiency, which may be considered either nutrient or drug claims according to how they are worded.13 Claims for nutritional supplements should not suggest that they may be used to promote health, stamina, strength, breeding, speed or show performance, or that they are superior to ordinary vitamin-mineral preparations because they are “chelated”, “time-released”, etc.6

In conclusion, FDA-CVM does not regulate oral supplements for animals under DSHEA. Oral supplements must provide nutritive value, which has been defined through national scientific bodies; otherwise the supplements will be considered drugs.  Pet food ingredients that have achieved FDA-CVM GRAS or FDA-CVM food additive status could be marketed as oral nutrient supplements, provided they have demonstrated nutritive value for the target species. Ingredients approved for use in human food are not automatically approved for use in animal feed; if they do not have nutritive value, they will be considered drugs. Appropriate claims for the supplements need to be developed with these limits in mind.

References

[1] Brown, L. P. (2010). Pet supplements roar. Pet Food Industry, September 2010, available at http://www.petfoodindustry.com/PrintPage.aspx?id=5956, site accessed December 10, 2010.

[2] Taylor, J. (2010). What the future holds for petfood and supplements. Pet Food Industry, October 2010, pp. 36 – 39.

[3] FDA (2009). Animal & Veterinary. Product Regulation. http://www.fda.gov/AnimalVeterinary/Products/AnimalFoodFeeds/ucm050223.htm, site accessed December 15, 2010.

[4] FDA (1996). Inapplicability of the dietary supplement health and education act to animal products. 61 FR 17706, April 22, 1996. http://federalregister.gov/a/96-9780, site accessed December 15, 2010.

[5] OTC in this statement refers to “over-the-counter”.

[6] FDA (1995). Inspections, Compliance, Enforcement, and Criminal Investigations. CPG Sec 690.100 Nutritional Supplements for Companion Animals. http://www.fda.gov/ICECI/ComplianceManuals/CompliancePolicyGuidanceManual/ucm074708.htm, site accessed December 9, 2010.

[7] Burdock, G.A. and Matulka, R. A. (2009). The Future of Dietary Supplements as Pet Food Ingredients, Sept 16, 2009 edition, Natural Products Insider, available at http://www.naturalproductsinsider.com/articles/2009/09/the-future-of-dietary-supplements-as-pet-food-ingredients.aspx, site accessed December 9, 2010.

[8] National Research Council (2006). Nutrient Requirements of Dogs and Cats. National Academies Press, Washington, DC.

[9] National Research Council (2007). Nutrient Requirements of Horses, Sixth Revised Edition. National Academies Press, Washington, DC.

[10] Association of American Feed Control Officials Incorporated (AAFCO) (2010). 2010 Official Publication.

[11] A not-for-profit corporation formed in April 2002 to promote acceptance of dietary supplements for animals by FDA

[12] National Animal Supplement Council (NASC) (2010). Regulation of animal health supplements- a historical summary, available at http://nasc.cc/index.php?option=com_content&task=view&id=19&Itemid=41, site accessed December 10, 2010.

[13] Benz, S. (2009).   FDA’s regulation of pet food.  FDA Center for Veterinary Medicine, Division of Animal Feeds, available at http://www.fda.gov/AnimalVeterinary/ResourcesforYou/ucm047111.htm, site accessed December 10, 2010.

[14] FDA (2007). New animal drug determination. Center for Veterinary Medicine, Program Policy and Procedures Manual, Guide 1240.3500, available at http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/PoliciesProceduresManual/UCM046797.pdf, site accessed December 10, 2010.