By Courtney Cavaliere

Many men and women know that they can take natural remedies such as echinacea (Echinacea spp., Asteraceae) to help ward off colds or valerian (Valeriana officinalis, Valerianaceae) to combat anxiety. In increasing numbers, pet owners have begun to realize that similar natural supplements are also available to treat their sneezing Labradors or to calm their high-strung tabbies.

Recent market statistics indicate that sales of supplements for companion animals* are on the rise. Tinctures, tablets, and powders designed to supplement the diets and treat the ailments of humankind’s furry friends are increasingly available, despite on-going regulatory challenges. These products are expected to experience continued growth in the near future, indicating that the supplement industry may quickly be “going to the dogs.”

The Pet Supplement Market

Nutrition Business Journal (NBJ) has estimated that US pet supplement sales reached $923 million in 2007, an increase of 8% over 2006 sales (See Figure 1).¹ NBJ found that the overall natural pet and pet nutrition market (defined as pet supplements, natural and organic pet foods, and pet supplies and other products) exceeded $2.1 billion in 2007, of which supplements accounted for 43% of sales.

Research published recently by Packaged Facts, meanwhile, estimated US retail sales of pet supplements and nutraceutical treats at $1.2 billion in 2007, with 74% of this figure representing supplement sales.² According to the Packaged Facts report, the majority of pet supplements (51%) are purchased for horses, while dog supplements represent 38% of the market and cat supplements represent 6%.

The company Native Remedies (Boca Raton, FL), which has manufactured natural supplements and treatments for men and women since its founding in 2002, launched a line of supplements for dogs and cats under the brand name PetAlive® in 2005. PetAlive products are compound formulas consisting of herbal and other natural ingredients, as well as a range of homeopathic remedies. According to George Luntz, president and co-founder of Native Remedies, sales of PetAlive products have more than tripled over the past few years. “The growth rate has pretty much surpassed the rate of our human products—which are also rising,” said Luntz (oral communication, February 19, 2009). The company initiated a line of products for horses in March of 2009.

Many supplements for pets are based on or use herbal ingredients. According to William Bookout, president of the National Animal Supplement Council (NASC), probably 15% of the approximately 125 pet supplement companies that belong to NASC produce herb-specific supplements for dogs, cats, and horses (oral communication, November 10, 2008). He added that around 80% of NASC member companies probably use herbs as ingredients in some of their product formulas.

Greg Tilford, president of Animal Essentials (Victor, MT), stated that herbal supplements for animals have definitely become a fast-growing market niche. Animal Essentials established a line of herbal medicinal pet products under the brand name Animals’ Apawthecary in 1995, and the company now produces over 40 single-herb extracts in a glycerin or mild alcohol base and over 15 combination formulas in liquids as botanical supplements for pets. According to Tilford, Animal Essentials’ product line has experienced double-digit growth almost every year since its inception (G. Tilford, oral communication, October 28, 2008).

The latest annual meeting of the American Holistic Veterinary Medical Association (AHVMA), held in October of 2008, also gave an indication that there is growing availability of herbal veterinary products. According to Nancy Scanlan, DVM, president of the Veterinary Botanical Medical Association (VBMA) and a veterinarian at the Sherman Oaks Veterinary Group in California, about one-third of the exhibitors at the meeting were herbalists (oral communication, October 27, 2008).

Dr. Scanlan added that the rise in associations supporting complementary and alternative medicine techniques for animals reinforces growth in the field of alternative healthcare for pets. Over the past 2 decades, the number of associations supporting the use of acupuncture for animals has increased from 1 to 3. The VBMA, an education-based organization dedicated to promoting the responsible use of herbal medicine for animals, was founded in 2002.

Many factors have been fueling growth in the pet supplement industry. Pet ownership, for instance, is on the rise.¹ According to the 2007-2008 National Pet Owners Survey, 63% of US households own a pet, whereas 56% of households owned a pet when the survey was first conducted in 1988.³

Luntz noted that more and more people throughout the world have begun to take an interest in using natural treatment options to care for their own health, as well as the health of their families. “Pets are pretty much part of our families,” he explained. “It makes sense that people would want to include them in their quest for healthier living.”

“There is now very strong awareness that the food supply is not what it used to be and that there is a need for people to supplement their diets. That carries over for animals, as well,” said Tom Cameron, DVM, veterinary technical support for Standard Process Inc. (Palmyra, WI), a company that manufactures nutritional whole food supplements for both humans and animals (oral communication, February 16, 2009). “A lot of health conditions are caused by nutritional deficiencies, and foods for animals, in particular, are highly processed.”

Use of supplements for animals is also rising due to the growing recognition of their effectiveness and gentleness, particularly in comparison to some pharmaceuticals. “In my practice, almost every animal I see goes out the door with some herbs,” said Dr. Scanlan. “I use herbs both because of situations where they are more effective than Western medicine and situations where they have less side effects than Western medicine.”

Dr. Scanlan noted that, for instance, there are no conventional pharmaceutical medications that are particularly effective for treating prostate problems in animals, and herbal supplements are therefore a good choice for veterinarians confronted with this condition. She has found that saw palmetto (Serenoa repens, Arecaceae), either alone or with Chinese herbal formulas, often helps where Western medicine is less effective. She also frequently recommends herbal treatments for animals with arthritis, since herbal medications do not have the adverse effects on liver and kidneys that are often associated with pharmaceuticals.

Regulation of Supplements for Pets

Supplements for pets have been able to achieve impressive strides in the marketplace despite a complicated legal status and a lack of formal regulations.

The Dietary Supplement Health and Education Act of 1994 (DSHEA) established regulations for human dietary supplements at a time when there were few similar products for pets on the market.⁴ DSHEA did not specifically address the topic of supplements for pets, but a posting in the Federal Register later specified that the US Food and Drug Administration (FDA) does not consider such supplements to be covered under DSHEA.⁵ Supplements marketed for dogs, cats, and horses have therefore been left with 2 possible legal categories under US law—they may be defined as animal foods/feeds or animal drugs.^4,6

Most supplement products for pets are classified by the manufacturers as nutritional or feed supplements. However, hundreds of ingredients commonly used for human and pet dietary supplements are not technically approved for use in animal feed products.

The other regulatory option for pet supplements, as animal drugs, requires that supplement marketers submit a New Animal Drug Application to the FDA’s Center for Veterinary Medicine (CVM), demonstrating the product’s safety and efficacy according to certain criteria. According to Book-out, these applications, and the testing that they require, are expensive and problematic. In particular, companies cannot recover the considerable costs incurred through product development and testing, since, in most cases, natural substances cannot be patented. Many animal supplements are thus discouraged from even attempting to meet the criteria for “drug approval.”

Most supplements for animals are therefore considered animal feeds that contain unapproved ingredients or unapproved drugs, depending on intended use.⁷ Supplements for animals were nearly removed from the marketplace beginning in 2002, after the American Association of Feed Control Officials (AAFCO) organized a committee to develop an enforcement strategy for unrecognized, undefined animal feed ingredients, as well as accepted ingredients that were being marketed for unapproved uses.^†

The NASC (www.nasc.cc), however, which was established in 2002, was able to placate concerned consumers and regulators by initiating effective self-regulation measures for the pet supplement industry. The NASC, a nonprofit dedicated to providing a unified voice for animal health and nutritional supplement companies, immediately created quality control guidelines and instituted risk monitoring procedures for the industry.

Member companies of the NASC must use a written quality control manual, follow proper labeling guidelines, and implement an adverse event reporting system for tracking complaints and safety concerns.⁸ All NASC members must demonstrate their compliance with NASC protocols by having completed or scheduled an independent facility audit. Those companies that have successfully completed an audit are able to use the NASC Quality Seal on their products, Web sites, and advertisements, as a symbol to the public that the company conforms to strict quality standards. About 90% of companies that produce supplements for pets are members of NASC.¹

Animal Essentials is a member of NASC and conforms to the organization’s quality protocols. The company uses only human-grade ingredients, identifies all ingredients using at least US Pharmacopeia standards, and tests all materials for marker compounds, microbes, and shelf-life. “I think it’s safe to say that my company has higher standards than some companies selling similar products for humans,” said Tilford.

Standard Process is also a member of NASC and adheres to very high quality control standards. Standard Process tests products and ingredients multiple times throughout the manufacturing process in its onsite laboratory and participates in routine inspections by the FDA and regulating agencies. Dr. Cameron added that the ingredients used in the Standard Process Veterinary Formulas product line are also used in the company’s line of human products, and all of the products are developed in the same manufacturing facility. Both sets of products are therefore produced according to the same good manufacturing practices (GMPs) and high quality control standards.

Although not a member of NASC, Native Remedies performs rigorous testing on ingredients and produces both human and pet products according to the same GMPs and quality standards. The company also registers its manufacturers as approved food facilities and individually registers homeopathic medicines (including some PetAlive products) as over-the-counter products with the FDA.

Due to quality control and risk assessment efforts by the industry, the FDA-CVM currently regulates pet supplements with an intended use other than feed as unapproved drugs of low regulatory priority.⁷ However, Tilford stated that the industry will ultimately need more regulation. He argued that the pet supplement industry is currently in a situation similar to the one faced by the human dietary supplement industry before the passage of DSHEA. “It’s like being in the herbal industry 20 years ago,” said Tilford. “History is repeating itself.”

Bookout also stated that more regulation is bound to be implemented within the pet supplement industry in the future, and he claimed that such regulation is not necessarily detrimental to pet supplement companies or to the NASC. “Anybody who is a responsible participant within an industry should not be opposed to regulation that is fair, reasonable, responsible, and consistent,” said Bookout.

According to Bookout, the NASC has always been interested in achieving a viable long-term solution to the industry’s regulatory challenges.

“We work very cooperatively and very constructively with regulatory authorities at the federal and state level,” said Bookout. He explained that the FDA and state officials have expressed interest in ultimately formulating sufficient and consistent regulations for pet supplements, and the NASC intends to assist in those efforts and help ensure that future regulations are fair and responsible. “If we are not proactive in supporting that objective, then it will be defined for us. It’s better to shape your own destiny than to have it defined for you,” he said.

Twenty-one year-old gelding Rico was given a course of Standard Process’s veterinary formula Equine Metabolic Support. Before treatment, Rico was overweight, lame, had a fasting serum insulin of greater than 1600 units/mopl, and had fat pads—especially on the thorax and around his tail. After a month of treatment, he lost significant mass on his neck and the fat pads diminished, his fasting serum insulin dropped to 601 units, and he walked without evidence of pain. Equine Metabolic Support contains such ingredients as licorice (Glycyrrhiza glabra, Fabaceae) root, cinnamon (Cinnamomum verum, Lauraceae), and green tea (Camellia sinensis, Theaceae) extract. Photos © 2009 Standard Process.

Safety of Supplements for Pets

The actual and perceived safety of supplements for pets undoubtedly affects their sales in the marketplace. The FDA-CVM recently requested that the National Research Council of the National Academies investigate the safety of supplements for dogs, cats, and horses. The National Research Council convened a committee of experts to analyze this issue, and they released a report on the topic in 2008.⁹

The committee concluded that there is limited safety data for determining safe use of supplements for animals. The committee specifically assessed the safety of 3 supplements for dogs, cats, and horses—lutein (a carotenoid, usually derived from marigolds, Tagetes spp., Asteraceae), evening primrose (Oenothera biennis, Onagraceae) oil, and garlic (Allium sativum, Liliaceae). They discovered a lack of quality safety data on those supplements to determine safety in drugs and animal food additives, and they wrote that they could only report on historical safe intakes and estimate presumed safe intakes for the 3 animal supplements. The committee noted that supplements and ingredients considered safe in humans and other species are not always safe in horses, dogs, and cats. Excessive garlic, in particular, can cause hemolytic anemia in all 3 species. They recommended that clear and precise regulations for animal supplements be established, as well as a comprehensive adverse event reporting system that is not limited by membership or paid access and that generates accurate and reliable data.

Bookout issued a response to this report, in which he pointed out that the majority of the pet supplement industry belongs to NASC and participates in adverse event reporting through the organization.¹⁰ NASC member companies report all adverse events that they have received to the NASC on a monthly basis, and the NASC has built alerts into its system so that it is notified anytime a serious adverse event is reported by a member company (W. Bookout, oral communication, November 10, 2008). The organization’s NASC Adverse Event Reporting System (NAERS) can organize and retrieve data regarding adverse events according to company, product, or ingredient.

The NAERS system defines an adverse event broadly as any complaint for a product linked to a physical effect or health problem that may be (but is not necessarily) connected to or associated with use of the product—including transient events like vomiting, diarrhea, etc. According to the NAERS system, there have been, on average, 0.31 adverse events reported per million pet supplement administrations (dosage unit administered to an animal) sold by NASC member companies. NASC also collects information on serious adverse events, defined as any event with a transient incapacitating effect or a long-term or permanent health effect that requires follow-up with a veterinarian. According to the NAERS system, there have been, on average,

0.001 serious adverse events reported per million pet supplement administrations sold by NASC member companies.

Bookout noted that the incidence of adverse events is very low, particularly in light of the organization’s broad definition of adverse events. He added that companies’ and NASC’s adverse event reporting systems are important for vigilant risk management and for identifying early warning signs of potential dangers.

All NASC member companies also employ warning or cautionary statements in labeling for products that contain certain herbal ingredients, as recommended by the NASC Scientific Advisory Committee. For instance, supplements with garlic must include a cautionary statement in product labels advising consumers not to administer the product to a pet prior to surgery, since garlic can prolong bleeding and clotting time. Further, some herbal ingredients are banned from member companies’ products. Bookout explained that the FDA-CVM has recommended that kava (Piper methysticum, Piperaceae), comfrey (Symphytum spp., Boraginaceae), and pennyroyal (Mentha pulegium, Lamiaceae) oil not be used in pet food products, and the NASC has prohibited these herbal ingredients in supplements due to the agency’s recommendation. Kava has been associated with possible liver toxicity per some human case reports (although no causality has been confirmed), comfrey contains hepatotoxic pyrrolizidine alkaloids, and pennyroyal oil is thought to contain the toxin pulegone and has been linked to the death of one dog following dermal exposure according to a case report.¹¹

The Future of the Industry

NBJ has forecasted continued strong growth of the natural pet and pet nutrition market, of which supplements for animals are a key category. NBJ noted, however, that shifts are likely to occur in the types of supplements sold and the outlets through which supplements are sold.¹ Packaged Facts likewise has estimated that the industry of pet supplements and nutraceutical treats will experience continued growth. Caring for aging pet populations could generate particular market interest in the coming years.²

According to Dr. Scanlan, there is a need for more proof, more case studies, and more scientific evidence to support the growing field of botanical supplements for pets. She recommends that new-comers to the field collaborate with the VBMA and NASC as much as possible, and that they invest in efforts to educate veterinarians and consumers regarding the products they develop. “The more help I get from an herb company, the more likely I am to use their products,” she added.

†Many herbal ingredients have been given GRAS status by the FDA and AAFCO and are categorized as feed additives, with their intended use defined as “spices and other natural seasonings and flavorings” or “essential oils, oleoresins, and natural extractives.” When such ingredients are incorporated into an animal supplement with the purpose being to “effect the structure or any function of the body,” they are considered by regulatory agencies to be unapproved ingredients, thereby causing the product to be considered “adulterated.”