INTRODUCTION

Society is entering a new age for the modern family pet. Many owners today view their pet as a member of the family.¹ This change in mindset is altering the way in which animals are cared for as well. According to the American Pet Products Association, more than USD 58 billion was spent on pets in 2014, part of which could be attributed to prescription and OTC medications.² Projections estimated the total consumer expenditures to rise to $60.6 billion in 2015 and growth to continue in subsequent years.²

Community pharmacies are receiving an increasing number of pet prescriptions to meet the demands of the growing willingness to better care for pets.² Convenience, potential savings, changes in compounding regulations and crossover drugs (developed for humans but with accepted use in veterinary medicine) are driving this increase. Retailers are encouraging owners to pick up prescriptions for the whole family, pets included, at local pharmacies. Veterinary prescriptions often come without the hassle of dealing with insurance payers, meaning more profits and fewer interruptions in workflow. It seems only logical that companies would take advantage of this new view of pets as family members.

Unfortunately, pharmaceutical care provided by pharmacies to non-human species may not be as safe as pet owners would like. While the field of pharmacy has evolved significantly with pharmacists now completing a 4-year doctoral program, most are significantly under-qualified to dispense veterinary medications. To date, veterinary pharmacotherapy is not a mandatory element of any pharmacy education core curriculum.³ Yet the growth of pet prescriptions in retail pharmacy settings continues to soar.

Dogs and cats are anatomically, physiologically, and metabolically unique. A normal dosage given to a human could be far too much or too little to treat a pet, even when scaled based on weight (e.g. mg/kg). Even if given at an appropriate dosage for a pet, the presence of certain additives in some human drug formulations could be lethal. It is unlikely most pharmacists realize this, unfortunately, given their lack of veterinary pharmacotherapy education.³ To date there is no known research assessing the baseline knowledge of pharmacists as it pertains to potentially toxic substances for non-human patients. This study sought to fill that void by assessing the current knowledge level of practicing pharmacists with respect to toxic agents in veterinary patients.

METHODS

RESULTS

Participants were asked to select either a dog or a cat to establish a frame of reference and then answer all questions with this animal in mind. Results indicate six substances (macadamia nuts, chocolate, famotidine, loratadine, grapes and acetaminophen) resulted in statistically significant differences between dogs and cats (p<0.002). Cohen’s d effect size estimates ranged from 0.38 to 0.68 with most effect sizes approximating 0.50 in magnitude indicating a moderate effect size for each statistically significantly different pair. Table 2 provides a breakdown of full results and p-values based on participant responses by dog and cat.

Based on the species frame-point chosen, participants did not express significant concern for the ingestion of nine potential toxins (macadamia nuts, tea tree oil, loratadine, allium, English Ivy, xylitol, grapes, Sago Palm, and caffeine) and a heightened level of concern for a non-toxin (African Violet). Participants were therefore able to identify 15 of the 25 items listed as toxic to a dog of cat (60% accuracy).

An independent samples t-test was performed to compare responses by sex (Table 3). Of the 25 potential toxins, six yielded a statistically significant difference (p ≤ 0.002) after the Bonferroni adjustment (allium, pony tail palm, leather, grapes, DEET and ethanol). In all six instances, male pharmacists reported lower levels of concern on average than female pharmacists. Effect size estimates approximated 0.29 in magnitude, indicating a low-moderate effect size. Full results and p-values are presented in Table 3.

An ANOVA was performed to determine if participants’ responses varied by age. After a Bonferroni adjustment, five substances resulted in statistically significant differences (p<0.002) based on age (loratadine, moth balls, acetaminophen, caffeine and ethanol). Table 4 presents all results and p-values. In 15 instances, older pharmacists (age 50 years and older) were more likely to indicate concern for each potential toxin. Eta-squared effect size estimates indicated small (0.01) to moderate (0.06) effect sizes.⁴

Pharmacists’ responses were compared based on the setting in which they worked. Because only two pharmacists indicated they were Internet pharmacists, these responses were excluded from the ANOVA. A breakdown of results is presented in Table 5. Results indicate no statistically significant differences were discernible after a Bonferroni adjustment (p<0.002).

DISCUSSION

Participants in this study could correctly classify slightly more than one half of the listed items as toxic or non-toxic. For the purposes of discussion, a rating of 3.5 and above represents appropriate heightened concern for toxic exposure. The qualitative distinctions for ratings of 3 and 4 respectively were “somewhat” and “quite” concerned. We arbitrarily selected 3.5 as an appropriate cut-point to indicate where serious level of concern might lie. In this study, based on the species frame-point chosen, participants did not express adequate concern for the ingestion of several potential toxins (macadamia nuts, tea tree oil, loratadine, allium, English Ivy, xylitol, grapes, sago palm, and caffeine). Conversely, a rating of 3 or more for exposure to a non-toxic item was considered an inaccurate level of concern. As mentioned previously, a rating of 3 qualitatively represents “somewhat concerned.” Anything below this cutpoint (indicating “not at all concerned” or “slightly concerned”) was arbitrarily selected as an appropriate level of concern for a non-toxin. This occurred with only one of the listed items (African Violet). Based on these criteria, participants were able to correctly identify 15 of the 25 listed items as toxic to a dog or cat (60% accuracy).

Perhaps more concerning is that pharmacists achieved accuracy on just 50% of the pharmaceutical related items listed (acetaminophen, loratadine, famotidine and xylitol). When asked about xylitol, an artificial sweetener found in many products, including medications like gabapentin solutions, pharmacists ranked the consumption of xylitol by a dog as “somewhat concerning.” As the literature shows, xylitol consumption by a dog is considered a very serious poison emergency and can lead to hypoglycemia, liver failure, and even death.6 Just a small amount of xylitol (100 mg/kg) can elicit signs of toxicity, especially in smaller dogs.⁶

Dogs and cats were the chosen as the frame-point since they are the predominate species encountered in the community pharmacy setting. A comparison was made between the two to see if pharmacists could be discerning with respect to potential toxins. Some potential toxins are clinically important in both dogs and cats while others are important in only one species. The authors hypothesized that responses would not deviate significantly because pharmacists lacking veterinary toxicology training are unlikely to know which substances are poisonous for dogs, but not cats (and vice versa). Participants did indicate statistically significant different levels of concern (p<0.002) between dogs and cats for six substances (macadamia nuts, chocolate, famotidine, loratadine, grapes and acetaminophen). Of these items, acetaminophen would be the only potential toxin that has a clinically different level of concern based on species (dog versus cat).

Females in this study tended to express more concern for pets ingesting or being exposed to potential toxins. It is plausible that this is due to the humanistic nature of females to express more caution and concern.⁷ Younger participants tended to express less concern about the ingestion of a potential hazard. Again, this could be due to the humanistic nature of being less experienced with animals and situations that resulted in harm.⁸ There was no significant difference observed in responses based on the setting in which pharmacists work.

CONCLUSIONS

The findings of this investigation suggest that pharmacists are deficient in their understanding of veterinary pharmacology, particularly in regards to toxicology. Despite the increase in veterinary prescriptions in the community pharmacy setting, many pharmacists are deficient in their ability to advise on toxin exposure. Given human medications have consistently been responsible for the majority of pet poisoning cases in the United States (16%)⁹, it is paramount that pharmacists, particularly those in the community setting, have a baseline knowledge of which drug products and excipients cannot be safely administered to an animal.

While colleges of pharmacy still struggle to include veterinary pharmacotherapy in the pharmacy curriculum, there are select groups of pharmacists who are specially trained in veterinary pharmacy. Organizations such as the Society of Veterinary Hospital Pharmacists (SVHP) and the American College of Veterinary Pharmacists (ACVP) offer training and educational opportunities to the rest of the pharmacy profession. Through their continued work and increasing awareness of pet ownership, it is possible that community pharmacies will soon acquire the competence to provide appropriate non-human patient care.