Toxicology of Frequently Encountered Nonsteroidal Anti-inflammatory Drugs in Dogs and Cats: An Update.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used for their antipyretic, anti-inflammatory, and analgesic properties. Although most NSAIDs consist of a range of pharmacologically active agents with diverse chemical structures and properties, they have similar therapeutic and adverse effects associated with their use. Each year, the American Society for the Prevention of Cruelty to Animals Animal Poison Control Center (APCC) receives hundreds of cases involving acute accidental ingestion/overdose of NSAIDs in dogs and cats. This article provides an overview on the classification, uses, pharmacokinetics, mechanisms of action, and treatment of the most commonly encountered NSAIDs in dogs and cats.

Mirtazapine toxicity in cats: retrospective study of 84 cases (2006-2011).

Objectives Mirtazapine is commonly used in veterinary medicine at doses of 1.88 or 3.75 mg as an appetite stimulant. The objectives of this study were to determine the most common adverse effects reported and the dose associated with these signs. Methods Records of cats with mirtazapine exposure (2006-2011) were obtained from the American Society for the Prevention of Cruelty to Animals' Animal Poison Control Center. The following parameters were recorded: signalment, weight, outcome, agent ingested, amount ingested, route of exposure, clinical signs observed, intended of use, onset time of signs and duration of signs. Results The 10 most commonly observed adverse effects reported in 84 cats exposed to mirtazapine included vocalization (56.0% of cats; mean dose 2.56 mg/kg), agitation (31.0%; 2.57 mg/kg), vomiting (26.2%; 2.92 mg/kg), abnormal gait/ataxia (16.7%; 2.87 mg/kg), restlessness (14.3%; 3.55 mg/kg), tremors/trembling (14.3%; 2.43 mg/kg), hypersalivation (13.0%; 2.89 mg/kg), tachypnea (11.9%; 3.28 mg/kg), tachycardia (10.7%; 3.04 mg/kg) and lethargy (10.7%; 2.69 mg/kg). Fifty-nine (70.2%) cases were considered accidental ingestions and 25 (29.8%) cases were given mirtazapine as prescribed. The doses associated with signs of toxicity were 15.00 mg (40 cats), 3.75 mg (25 cats), 7.50 mg (four cats), 30.00 mg (one cat), 18.75 mg (one cat), 11.25 mg (one cat), 5.80 mg (one cat) and 1.88 mg (one cat). For cats with available information, the onset of clinical signs ranged from 15 mins to 3 h, and time to resolution of clinical signs ranged from 12-48 h. Conclusions and relevance The greater number of adverse effects at 3.75 mg rather than 1.88 mg suggests that the latter may be a more appropriate starting dose for stimulating appetite while limiting toxicity. The benefit of dispensing exact doses of mirtazapine is implied given the likelihood of accidental administration of a full tablet (15 mg) and the resulting toxicity.

Suspected synthetic cannabinoid toxicosis in a dog.

OBJECTIVE: To describe the effects of suspected synthetic cannabinoid (SC) toxicosis and the response to intravenous lipid emulsion (ILE) therapy in a dog. CASE SUMMARY: A 2-year-8-month-old male Boxer dog was evaluated at an emergency hospital for progressive ataxia and inappropriate mentation. The initial physical examination identified marked hypothermia (32.7°C [90.9°F]), intermittent sinus bradycardia (60/min), stuporous mentation with intermittent aggression, and severe ataxia. Neurologic status deteriorated to comatose mentation within 2 hours of presentation. The initial diagnostic evaluation (eg, CBC, serum biochemistry profile, venous blood gas, and electrolyte determination) revealed a respiratory acidosis and thrombocytopenia. The owner reported that the dog was exposed to an SC containing Damiana leaf, Marshmallow leaf, and Athaea leaves. Initial treatment included IV fluids and supplemental oxygen. Mechanical ventilation was provided due to hypoventilation and periods of apnea. Intravenous lipid emulsion therapy was administered as a bolus (1.5 mL/kg) and continued as a continuous rate infusion (0.5 mL/kg/h) for a total of 6 hours. The dog became rousable and was weaned from mechanical ventilation approximately 15 hours following presentation. The dog was eating and walking with no ataxia, had a normal mentation at approximately 33 hours following presentation, and was discharged home at that time. Communication with the owners 5 days following discharge revealed that the dog was apparently normal. NEW OR UNIQUE INFORMATION PROVIDED: Based on this case and other reports in the literature regarding human exposures, SC ingestion may result in more severe clinical signs than marijuana ingestion in dogs. Significant clinical intervention may be necessary. Intravenous lipid emulsion treatment may be beneficial due to the lipophilicity of SC.

Concentrated tea tree oil toxicosis in dogs and cats: 443 cases (2002-2012).

OBJECTIVE: To determine the frequency, types, and severity of clinical signs; geographic distribution; and treatment information associated with toxicosis caused by 100% tea tree oil (TTO) in dogs and cats in the United States and Canada. DESIGN: Retrospective case series. ANIMALS: 337 dogs and 106 cats with evidence of exposure to 100% TTO. PROCEDURES: 10-year incident data were retrieved from the ASPCA Animal Poison Control Center database from January 2002 to December 2012. Only evidenced or witnessed incidents assessed as toxicosis or suspected toxicosis were included. Signalment, amount of TTO used, intention of use, and outcome information were evaluated. Severity of illness and correlations with breed, sex, age, and weight were determined. RESULTS: TTO was intentionally used in 395 of 443 (89%) animals. The amount used ranged from 0.1 to 85 mL. Incidents were reported from 41 states, the District of Columbia, and 4 Canadian provinces. Exposure route was cutaneous in 221 (50%) animals, cutaneous and oral in 133 (30%), and oral in 67 (15%). Clinical signs developed within 2 to 12 hours and lasted up to 72 hours. The most common signs were increased salivation or drooling, signs of CNS depression or lethargy, paresis, ataxia, and tremors. A significant association with severity of illness was found for age and weight, with higher prevalence of major illness in younger and smaller cats. CONCLUSIONS AND CLINICAL RELEVANCE: Intentional or accidental use of 100% TTO in dogs or cats caused serious signs of CNS depression, paresis, ataxia, or tremors within hours after exposure and lasting up to 3 days. Younger cats and those with lighter body weight were at greater risk of developing major illness.

A review of 29 incidents involving 4-aminopyridine in non-target species reported to the ASPCA Animal Poison Control Center.

4-Aminopyridine (4-AP) is an avicide used in products that are approved by the Environmental Protection Agency (EPA) to control populations of various birds. Pharmaceutical 4-AP is also used in humans to treat neural and muscular dysfunctions associated with multiple sclerosis. Although strict restrictions for its use are in place, exposures to 4-AP bait by non-target species still occur. Twenty-nine exposures of 4-AP bait involving non-target species were identified and retrieved from the ASPCA Animal Poison Control Center medical record database. Canines were the most commonly exposed (86 %) species followed by felines (10 %). The highest frequency of exposures was reported from Colorado (22 %). Most commonly reported clinical signs in canines were tremors, hypersalivation, seizures, tachycardia, and ataxia. The onset time of signs ranged from 5 to 300 min with an average of 89 min. Clinical signs lasted from 15 to 84 h with an average of 37 h. Patient outcome was known in six cases; one dog died 4 h after the exposure and five made full recovery with supportive care. Treatment of five surviving patients included administration of activated charcoal, use of anticonvulsants and muscle relaxants like diazepam and methocarbamol, and intravenous fluids. Diagnosis of 4-AP toxicosis can be supported by testing the gastric contents of the exposed patient. Due to the rapid absorption, samples need to be collected and frozen/chilled promptly. For successful patient outcome, treatment must be implemented quickly after an exposure.

Effectiveness and adverse effects of the use of apomorphine and 3% hydrogen peroxide solution to induce emesis in dogs.

OBJECTIVE: To determine the effectiveness and adverse effects of apomorphine and 3% hydrogen peroxide solution used for emesis in dogs. DESIGN: Prospective observational study. ANIMALS: 147 dogs that received apomorphine (IV or placed in the conjunctival sac) or 3% hydrogen peroxide solution (PO) to induce emesis after exposure to toxic agents. PROCEDURES: Data regarding signalment; agent information; type, dose, route, and number of emetic administrations; whether emesis was successful; number of times emesis occurred; percentage of ingested agent recovered; and adverse effects were collected via telephone during American Society for the Prevention of Cruelty to Animals Animal Poison Control Center operations and stored in a database for analysis. Mann-Whitney and Fisher exact tests were used to evaluate emetic success rates. RESULTS: Apomorphine and 3% hydrogen peroxide solution successfully induced emesis in 59 of 63 (94%) and 76 of 84 (90%) of dogs, respectively. Mean time to onset of emesis after the first dose of emetic was 14.5 and 18.6 minutes when hydrogen peroxide (n = 37) and apomorphine (31) were used, respectively, with mean durations of 42 and 27 minutes, respectively. Mean estimates for recovery of ingested agents were 48% for hydrogen peroxide and 52% for apomorphine. Adverse effects were reported in 16 of 112 (14%) dogs for which information was available. CONCLUSIONS AND CLINICAL RELEVANCE: 3% hydrogen peroxide solution and apomorphine effectively induced emesis in dogs when used as directed. Emesis occurred within minutes after administration and helped recover substantial amounts of ingested agents. Adverse effects of both emetics were considered mild and self-limiting.

Adverse reactions from essential oil-containing natural flea products exempted from Environmental Protection Agency regulations in dogs and cats.

OBJECTIVE: To describe adverse effects in dogs and cats exposed to Environmental Protection Agency exempted plant-derived flea preventatives containing mixtures of essential oils. DESIGN: Retrospective study from 2006 to 2008. SETTING: Records of dog and cat cases were reviewed from the American Society for the Prevention of Cruelty to Animals, Animal Poison Control Center database. ANIMALS: Thirty-nine cats and 9 dogs with history of exposure to natural flea preventatives. MEASUREMENTS AND MAIN RESULTS: The following information was retrieved from each incident: number of animals, species involved, frequency, types, onset time, duration of clinical signs, exposure appropriateness, final outcome, and treatment information. Ninety-two percent of animals (n = 44) showed presence of one or more adverse effects. The frequency of adverse effects in dogs (n = 8; 89%) and cats (n = 36; 92%) was similar. Onset time of adverse effects in 39 of 44 animals occurred within 24 hours. The duration of signs in 24 animals ranged from 30 minutes to 149 hours. The products were used as per label in 77% animals (n = 37). Of 28 animals with known outcome, 50% (n = 14) recovered with bathing alone while others received intravenous fluids, muscle relaxants, and anticonvulsive medications. Death (1 cat; n = 1/28; 4%) or euthanasia (1 cat and 1 dog; n = 2/28; 7%) was reported in 3 animals. CONCLUSION: Dogs and cats can experience significant adverse effects when exposed to plant-derived flea preventatives even when used according to label directions. The number of reports of exposure in cats was higher than dogs, but the frequency of reported adverse effects was similar between the 2 species. Agitation and hypersalivation were common in cats, whereas lethargy and vomiting were common in dogs.

An overview of trends in animal poisoning cases in the United States: 2002-2010.

Veterinary toxicology is a constantly evolving field. The authors use the ASPCA Animal Poison Control Center's medical record database to examine recent trends in veterinary toxicology/animal poisoning incidents received from 2002 to 2010. The demographics of animals exposed to potentially harmful substances, the types of substances ingested, changes/emerging trends in substance exposures, and trends in therapies used to treat exposures are discussed.

Toxicology of frequently encountered nonsteroidal anti-inflammatory drugs in dogs and cats.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of heterogeneous compounds extensively used in both human and veterinary medicine for their antipyretic, anti-inflammation, and analgesic properties. NSAIDs consist of a wide range of pharmacologically active agents with different chemical structures, with similar therapeutic and adverse effects. The ASPCA Animal Poison Control Center received 22,206 NSAID incidents in dogs and cats (3% of total cases; dogs [15,823] and cats [1244]) during 2005 to 2010. This is roughly equivalent to 4% NSAID incidents reported in humans. The most common NSAID involved was ibuprofen, followed by aspirin, naproxen, deracoxib, meloxicam, diclofenac, piroxicam, indomethacin, nabumetone, and etodolac. This article provides a brief overview of classification, mechanism of action, pharmacologic and toxicologic properties, and treatment information involving frequently encountered human and veterinary NSAIDs in dogs and cats.

Tobacco and cigarette butt consumption in humans and animals.

Discarded cigarette butts may present health risks to human infants and animals because of indiscriminate eating behaviours. Nicotine found in cigarette butts may cause vomiting and neurological toxicity; leachates of cigarette butts in aquatic environments may cause exposure to additional toxic chemicals including heavy metals, ethyl phenol and pesticide residues. This report reviews published and grey literature regarding cigarette butt waste consumption by children, pets and wildlife. Although reports of human and animal exposures number in the tens of thousands, severe toxic outcomes due to butt consumption are rare. Nonetheless, the ubiquity of cigarette butt waste and its potential for adverse effects on human and animal health warrants additional research and policy interventions to reduce the stream of these pollutants in the environment.