Thawley VJ , Drobatz KJ . Assessment of dexmedetomidine and other agents for emesis induction in cats: 43 cases (2009-2014) . J Am Vet Med Assoc . 2015 ; 247 ( 12 ): 1415 - 1418 . doi: 10.2460/javma.247.12.1415
Willey JL , Julius TM , Claypool SP , Clare MC . Evaluation and comparison of xylazine hydrochloride and dexmedetomidine hydrochloride for the induction of emesis in cats: 47 cases (2007-2013) . J Am Vet Med Assoc . 2016 ; 248 ( 8 ): 923 - 928 . doi: 10.2460/javma.248.8.923 Teriparatide
Thies M , Bracker K , Sinnott V . Retrospective evaluation of the effectiveness of xylazine for inducing emesis in cats: 48 cats (2011-2015) . J Vet Emerg Crit Care (San Antonio) . 2017 ; 27 ( 6 ): 658 - 661 . doi: 10.1111/vec.12641
Nystrom MR , Odunayo A , Okafor CC . Assessment of hydromorphone and dexmedetomidine for emesis induction in cats . J Vet Emerg Crit Care (San Antonio) . 2019 ; 29 ( 4 ): 360 - 365 . doi: 10.1111/vec.12866
Colby ED , McCarthy LE , Borison HL . Emetic action of xylazine on the chemoreceptor trigger zone for vomiting in cats . J Vet Pharmacol Ther . 1981 ; 4 ( 2 ): 93 - 96 . doi: 10.1111/j.1365-2885.1981.tb00716.x
Plumb DC . Hydromorphone . Plumb’s Veterinary Drugs . Accessed February 26, 2023. https://app.plumbs.com/drug-monograph/UvzrLrOaaCPROD?source=search&searchQuery=hydromorphone
Kirchofer KS , Block G , Johnson JA . Efficacy of intravenous administration of apomorphine for removal of gastric foreign material in dogs: 495 cases (2010-2015) . J Am Vet Med Assoc . 2019 ; 255 ( 4 ): 459 - 465 . doi: 10.2460/javma.255.4.459
Khan SA , McLean MK , Slater M , Hansen S , Zawistowski S . Effectiveness and adverse effects of the use of apomorphine and 3% hydrogen peroxide solution to induce emesis in dogs . J Am Vet Med Assoc . 2012 ; 241 ( 9 ): 1179 - 1184 . doi: 10.2460/javma.241.9.1179
To prospectively assess the efficacy of emesis induction for the recovery of gastric foreign objects in cats and to determine if any factors influenced recovery.
Cats for which emesis induction was deemed appropriate were administered an emetic agent by the attending clinician between October 2018 and April 2021. Data collected included whether emesis was successful in recovery in some or all of the foreign object, time from administration to emesis, number of emetic events, and type, length, width, and surface area of the material ingested.
Of the 22 cats that had emesis attempted, 11 (50%) vomited some or all of the foreign object. The time from ingestion to presentation, time from the last meal, presence of food in the vomitus, type of the object, and length, width, and surface area of the object did not influence the likelihood of successful recovery with emesis induction. The most common object cats ingested were rubber bands.
Recovery of gastric foreign objects in cats with emesis induction alone may be successful 50% of the time. The type and size of the object is unlikely to influence whether or not emesis will be successful. This information can help prepare cat-owners for expectations and outcomes following attempts at emesis induction.
To prospectively assess the efficacy of emesis induction for the recovery of gastric foreign objects in cats and to determine if any factors influenced recovery.
Cats for which emesis induction was deemed appropriate were administered an emetic agent by the attending clinician between October 2018 and April 2021. Data collected included whether emesis was successful in recovery in some or all of the foreign object, time from administration to emesis, number of emetic events, and type, length, width, and surface area of the material ingested.
Of the 22 cats that had emesis attempted, 11 (50%) vomited some or all of the foreign object. The time from ingestion to presentation, time from the last meal, presence of food in the vomitus, type of the object, and length, width, and surface area of the object did not influence the likelihood of successful recovery with emesis induction. The most common object cats ingested were rubber bands.
Recovery of gastric foreign objects in cats with emesis induction alone may be successful 50% of the time. The type and size of the object is unlikely to influence whether or not emesis will be successful. This information can help prepare cat-owners for expectations and outcomes following attempts at emesis induction.
Ingestion of foreign objects in cats can prove to be a challenging presenting complaint to both general practitioners and emergency veterinarians. Gastric decontamination with the use of an emetic agent may prove clinically useful if a cat has ingested a foreign object. There are several studies in the veterinary literature that investigate emesis induction in cats. Many of these studies, however, focus on the pharmacologic agent used or compare various emetic agents to determine efficacy for inducing vomiting in the feline patient in a clinical setting.1–4 While these studies do describe whether cats vomited after administration of a certain emetic agent, only one reported outcome after emesis induction, but only for 61% of their patient population.2
Emesis induction may be a successful tool for gastric foreign object retrieval eliminating the need for more invasive options, like endoscopy or surgery. Although emesis induction is routinely used to attempt retrieval of gastric foreign objects, there is limited information in the veterinary literature on the success rate and factors associated with successful gastric foreign object retrieval in cats. Therefore, the goal of our prospective, observational study was to investigate the efficacy of emesis induction for the retrieval of gastric foreign objects in cats that were presented for witnessed or suspected foreign object ingestion. Additionally, we aimed to investigate historical, patient, and foreign object factors that may predict whether emesis induction will be successful or not. We hypothesized that the time from foreign object ingestion to emesis induction, the type and size of the object(s) ingested, and the time since the last known meal would be associated with the successful retrieval of gastric foreign bodies in cats.
Cats that were presented to the emergency service at the University of Pennsylvania’s veterinary teaching hospital between October 2018 and April 2021 that had a known or suspected foreign object ingestion and emesis induction was recommended by the attending clinician were included in the study. In cats with suspected foreign object ingestion, the owners reported their suspicion for ingestion including finding pieces of a toy missing, parts of an object chewed into pieces, or noticing an object missing.
To be included in the study, clinicians filled out a study-specific datasheet. Based on the attending clinician’s choice, an emetic agent was selected and administered. The type, dose, and route of administration of the emetic agent were recorded as observational data points. Historical data recorded included the time of ingestion, whether the ingestion was witnessed or not, time of last meal, and if this particular patient had a previous history of foreign object ingestion(s). If the time of ingestion was not known, an approximate time frame was provided by the owner. The authors chose the longest possible time from ingestion to emesis induction for statistical analysis.
For each cat, additional data collected included signalment, time from foreign object ingestion to emetic administration, number of emetic events, if there was any food present in the vomitus, and on which episode of vomiting the foreign object was retrieved, if at all. Foreign objects were categorized into 1 of 5 categories: fabric, metal, plastic, wood, or other. Whenever possible, if a foreign object was recovered, the percentage of the object recovered was categorized. The categories were: 0% to 25%, 26% to 50%, 51% to 75%, or 76% to 100%. To confirm the percentage of object recovered, the objects were provided to the cat owners for validation or owners provided an estimate or comparison object to determine the estimated total size of the object ingested. When a foreign object was recovered (either with emesis induction or endoscopic removal), data was collected on the type of object, length, width and surface area of the object, and the number of pieces recovered. Finally, the time from last meal to induction of emesis was calculated for each cat.
Following the initial emesis attempt, additional data were collected including whether other medications were administered for repeated attempts at emesis induction, complications of emesis induction, and if any additional treatments were performed. Additional treatments recorded included whether there was administration of an anti-emetic or reversal medication, if radiographs or ultrasound were obtained or if the cat had endoscopy or surgery performed. Outcome for each cat was recorded.
The Shapiro-Wilk test was used to assess continuous variables for normality. Descriptive statistics consisted of the mean ± SD (SD) for normally distributed variables and the median (range) for variables that were not normally distributed. The count and percentage (%) were used to report frequency data. Dichotomous outcome variables were compared using the χ2 test when cell counts in the 2-by-2 contingency table were > 5; Fisher exact test was used when cell counts in the 2-by-2 contingency table were ≤ 5. Continuous outcome variables were compared using a 2-sample independent t-test for parametric data and a Wilcoxon rank sum test for nonparametric data. Bonferroni correction was applied to account for multiple comparisons where appropriate. For all comparisons, P < .05 was considered statistically significant. A commercial software program (STATA IC version 16.1; StataCorp LLC) was used for all statistical analyses.
Twenty-two cats were included in the study. The median age of all cats was 3.9 years (range, 0.4 to 14.8 years). Twelve (55%) cats were castrated males, 8 (36%) were spayed females, and 2 (9%) were intact males. Twenty (91%) cats were domestic shorthairs, 1 (5%) cat was a Russian Blue, and 1 (5%) cat was a Siamese. The mean weight of all cats was 5.35 kg (SD ± 1.22 kg). Of the 22 cats included in the study, 18 (82%) had no prior history of foreign object ingestion, while 4 (18%) of them did. Among the 4 cats that had previous foreign object ingestions, 3 (75%) cats had passed that previous foreign object in the feces, while 1 (25%) cat had a successful foreign object recovery with emesis.
The median time from witnessed (14 cats) or suspected (8 cats) foreign object ingestion to the induction of emesis was 52.5 minutes (range, 1.3 to 720 minutes; Table 1). The median time from a last known meal to attempt at emesis induction was 4.5 hours (range, 1 to 18 hours). Nineteen (86%) cats received dexmedetomidine at 7 mcg/kg (18 IM, 1 IV) and 3 (14%) cats received hydromorphone SQ (2 cats: 0.1 mg/kg, 1 cat: 0.01 mg/kg) for emesis induction. Fourteen cats (14/22 [64%]) vomited following initial administration of an emetic agent. Of those 14 cats, 13 of them received dexmedetomidine and only 1 received hydromorphone.
Time from ingestion to emesis and number of cats that vomited in cats with witnessed versus cats with suspected foreign object ingestions.
Cats vomited a mean of one time (SD ± 1). Of the cats that vomited, 57% had food in their vomit and 43% of cats did not. Emesis induction was repeated in 3 (14%) cats that did not vomit after initial induction of emesis: 1 cat initially received dexmedetomidine 7 mcg/kg IM, 1 cat received hydromorphone 0.01 mg/kg SC and 1 cat received hydromorphone 0.1 mg/kg SC. The 2 cats that received hydromorphone initially were then administered 7 mcg/kg dexmedetomidine IM and the cat that received dexmedetomidine initially was then administered 0.1 mg/kg hydromorphone SQ. None of the cats vomited with repeated emesis induction. Following emesis induction, 1 (5%) cat received a dose of maropitant, and 2 cats (9%) received atipamezole for reversal of dexmedetomidine. Information pertaining to complications related to emesis induction was available in 14 cats. Seven cats (50%) had no complications reported while 7 cats (50%) had sedation listed as a complication. There was no incidence of choking or aspiration pneumonia noted.
Foreign objects were successfully retrieved in 50% of cats (11/22) with emesis induction (Table 2). Eight out of the 11 cats vomited the foreign object after vomiting once. For 2 cats, the foreign object was recovered after vomiting twice and for 1 cat, the foreign object was recovered after vomiting 3 times. Of the 11 cats that vomited a foreign object with emesis induction, 100% of cats vomited a single type of item. Seven of the 11 cats with successful foreign object recovery were witnessed ingestions, while the other 4 were suspected ingestions. The 3 other cats that vomited after emesis induction did not vomit a foreign object. All 3 of those cats were presented to the emergency service for witnessed foreign object ingestions.
Summary of percentage of foreign object recovered with emesis induction in the 11 cats that vomited the foreign material.
Of the 11 (50%) cats that did not have successful retrieval of their foreign object with emesis induction, 4 proceeded to endoscopy for retrieval. One cat (5%) that had successful induction of emesis also went on to have endoscopy. This cat vomited 26-50% of the foreign object (hair ties) and then went on to have the remaining pieces removed endoscopically. The number of additional hair ties recovered at the time of endoscopy was not recorded in this cat. The remaining 7 cats that did not vomit the foreign object did not have any additional procedures attempted to remove the foreign object and were discharged home. Six of those cats did not return for re-evaluation for the foreign object ingestion. One cat returned the following day and had an abdominal ultrasound, which showed a linear foreign body obstruction. This cat had a successful gastrotomy, matted yarn and hair were removed, and was discharged home.
The most common type of object recovered with emesis induction was a rubber band or hair tie and was identified in 6 (6/11 [55%]) cats. The most common type of object not recovered was also a rubber band or hair tie, present in 4 (36%) cats with unsuccessful foreign object retrieval with emesis induction. A summary of the types of items ingested and recovered are provided (Tables 2 and 3).
Summary of types of foreign objects recovered with emesis induction and/or endoscopy divided into cats with witnessed and suspected foreign object ingestions.
The median maximal diameter of successfully recovered objects using emesis induction was 11.43 cm (range, 1 cm to 100 cm). The median maximal diameter of unsuccessfully recovered objects (measured after endoscopic removal) was 6.31 cm (range, 0.635 to 68.6 cm). The median approximate surface area (length x width) of successfully recovered objects with emesis induction was 9.525 cm2 (range, 0.8 cm2 to 2000 cm2). The median approximate surface area (length x width) of unsuccessfully recovered objects with emesis induction alone was 7.125 cm2 (range, 0.4 cm2 to 174.244 cm2). A summary of case details is included (Supplementary Table S1).
Diagnostic investigation and treatment options before and after emesis induction were based on clinician discretion and owner preferences. Four (18%) cats had abdominal radiographs obtained prior to the induction of emesis and 4 (18%) cats had abdominal radiographs obtained after the induction of emesis. There was no association between an unsuccessful foreign object retrieval and obtaining abdominal radiographs after an attempt at induction of emesis (P = .311).
Evaluation of factors that may be associated with successful foreign object retrieval was investigated. There was no association between time from foreign object ingestion to the induction of emesis (P = 1), time elapsed from the last meal (P = 1) or the presence of food in the vomit (P = 1; α = .01). Additionally, neither the emetic agent used (P = .311), a repeated attempt at emesis (P = .214), nor sedation following emesis induction (P = .07) were associated with recovery of the foreign object. The type of foreign object ingested was also not associated with successful retrieval (P = 1) nor was there an association between maximal diameter (P = 1) or approximate surface area (P = 1) and successful foreign object retrieval after emesis induction (α = .01). Additionally, age (P = .18), sex (P = 1), breed (P = 1), and body weight (P = 1) were not associated with successful retrieval of the foreign object (α = .013).
This prospective study is the first to evaluate the efficacy of gastric foreign object recovery in cats with emesis induction and factors that may be associated with successful retrieval. The results indicated that the use of emesis induction in cats for the recovery of some or all gastric foreign objects was successful in 50% of cats. While emesis was achieved in 14/22 cats which is consistent with previous studies, recovery of gastric foreign objects was only successful in 11 cats.
The only 2 emetic medications administered in the present study were dexmedetomidine and hydromorphone. Dexmedetomidine, an α-2 adrenergic receptor agonist, induces vomiting in cats centrally via agonism of α-2 receptors in the chemoreceptor trigger zone.5 Hydromorphone, a pure mu opioid receptor agonist, also promotes emesis via stimulation of the chemoreceptor trigger zone.6 Based on the present study, the choice of emetic agent did not affect successful foreign object retrieval. It is important to note that dexmedetomidine was administered as a first line emetic more frequently (86% of the time). This may be related to a previous study in cats evaluating the overall efficacy of dexmedetomidine as an emetic agent1 and is the preferred emetic medication at our institution. Larger prospective, randomized controlled studies are needed to investigate whether different emetic agents are associated with successful foreign object recovery.
On average cats vomited one time after administration of either dexmedetomidine or hydromorphone (range, 0 to 3). This range is similar to results from another study that evaluated different emetic agents in cats. According to the study on vomiting in purpose bred cats by Nystrom et al, cats that received hydromorphone vomited between 0 and 2 times and cats that received dexmedetomidine vomited 0 to 5 times.4 In the present study, 8 of the 11 cats that vomited their gastric foreign object did so after vomiting once. The 3 subsequent cats had successful recovery of the foreign object after vomiting either 2 or 3 times. The ability to induce more than 1 emetic event could increase the likelihood of successful foreign object recovery. In our study, 3 cats were administered additional medication for emesis induction when the first emesis attempt was unsuccessful. In these 3 cats, the second attempt was also unsuccessful in inducing vomiting which could suggest that additional attempts at medication induced vomiting is futile, could increase the potential risk for complications, and should not be recommended in cats.
Time from foreign object ingestion to attempt at emesis induction was not associated with successful recovery of the gastric foreign object in cats. The median time from ingestion to presentation to the authors’ institution was 52.5 minutes. However, there was a wide range of time from foreign object ingestion to emesis induction with 1 cat having emesis induced 12 hours after ingestion. If the ingestion was unwitnessed (8 cats), owners gave an estimated time frame for the ingestion, which may have affected our study results. Cats with suspected foreign object ingestions had a median time to presentation that was nearly twice as long as cats with witnessed ingestions. In a study evaluating efficacy of apomorphine induced emesis for recovery of gastric foreign bodies in dogs, time from ingestion to recovery of the item was statistically significant.7 In this study,7 the successful recovery rate was highest for dogs in which emesis was induced within 2 hours of ingestion. This study, however, reported data for dogs only when an exact ingestion time was recorded. Given the small number of cats overall in our study with many of them having an estimated time of foreign object ingestion, it is possible that in a larger study including only cats with witnessed ingestions that a similar trend would be seen.
In this study, the presence or absence of complications were recorded in 14 cats. Of those, 50% had no reported complications while the other 50% had sedation listed as a complication. Interestingly, only 2 cats received sedation reversals (both cats were administered a dose of atipamezole for dexmedetomidine reversal). In the retrospective study by Thawley et al, only 3 of 45 cats had sedation as a complication of emesis induction using xylazine or dexmedetomidine.1 In a different prospective study4 evaluating emesis induction in 12 cats, sedation scores were recorded after cats were administered hydromorphone or dexmedetomidine. In that report, dexmedetomidine proved to cause sedation, and higher sedation scores, in more cats than hydromorphone (83.3% vs. 8.3%, respectively).4 The difference between those studies and the present study is likely multifactorial. It is possible that some cats in the present study may have only been mildly sedate and therefore reversal was not deemed warranted. At our institution, is not standard of care to always administer a reversal agent after attempt at emesis with either dexmedetomidine or hydromorphone. Typically, administration of a reversal agent is reserved for cats that are showing adverse signs of sedation (ie, bradycardia, hypotension, hypoventilation, agitation). It is also possible that the 4 cats that had endoscopic foreign object retrieval were not given a reversal medication given the requirement for general anesthesia. In a study by Willey et al,2 92% of cats that received dexmedetomidine for emesis induction received atipamezole as a reversal. In this study, half the cats received doses of dexmedetomidine > 10 mcg/kg which is higher and could be more likely to cause sedation than the dose of dexmedetomidine (7 mcg/kg) used in our study.2
The time from the last meal and whether the vomited material contained food was not associated with successful recovery of the foreign object in our study. This may be because of the low number of cats in our study (type II error) or because food in the stomach is not associated with successful foreign object retrieval. To our knowledge, this is the first study in cats to directly investigate these factors. Interestingly, according to the American Society for the Prevention of Cruelty to Animals’ Animal Poison Control Center, it is typically recommended that dogs should be offered a small meal prior to induction of emesis unless they have eaten in the preceding 2-hour period because induction of emesis is more likely to be successful when there is food present in the stomach.8 This recommendation is based on expert opinion and to the author’s knowledge no prospective studies have been done. Larger prospective studies are needed to further investigate the effect of food in the stomach on successful gastric foreign object recovery in both dogs and cats.
The present study has some limitations. Despite being a prospective, observational study with data collected over 2 1/2 years at a busy academic urban hospital, the number of cats included was small. In the author’s experience this reflects clinical practice in that cats are less likely to be presented to a veterinary hospital for foreign object ingestion as compared to dogs. The doses of emetic agents were not standardized, but rather were chosen based on clinician preference. When an exact time of ingestion was not known, a time frame since ingestion was provided by the owners. The authors chose the longest possible time duration when a range was provided, which may not have been reflective of true events. Given that 8/22 cats in our study had unwitnessed ingestions and only 50% of them vomited a foreign object, it is possible that the other 50% of cats may not have eaten anything foreign at all. Induction of emesis is not recommended for removal of some types of foreign objects, specifically things like needles, hooks, or other sharp objects. Therefore, we cannot comment on the efficacy of emesis induction for recovery of all types of foreign objects in cats. Finally, medication history was not recorded for cats in this study and it is therefore possible that cats may have been administered routine or daily medications that could have interfered with successful emesis induction. It is reasonable to assume however, that if a cat was receiving an anti-emetic agent that emesis would not have been offered and therefore, this is unlikely to have affected our study results.
Results of the present study indicated that attempt at emesis induction with dexmedetomidine or hydromorphone for gastric foreign object recovery was safe but only effective 50% of the time. Unfortunately, the size or type of object, time from ingestion to emesis induction, and time from last meal proved not to be helpful in predicting successful recovery. Our study results are still helpful to advise cat owners with the relative likelihood of successful recovery of gastric foreign objects and better prepare them for the need for other interventions, like endoscopy or surgery.
Supplementary materials are posted online at the journal website: avmajournals.avma.org
The authors declare that there were no conflicts of interest. No third-party funding or support was received in connection with this study or the writing or publication of the manuscript. Funding sources did not have any involvement in the study design, data analysis and interpretation, or writing and publication of the manuscript.
Thawley VJ , Drobatz KJ . Assessment of dexmedetomidine and other agents for emesis induction in cats: 43 cases (2009-2014) . J Am Vet Med Assoc . 2015 ; 247 ( 12 ): 1415 - 1418 . doi: 10.2460/javma.247.12.1415
Willey JL , Julius TM , Claypool SP , Clare MC . Evaluation and comparison of xylazine hydrochloride and dexmedetomidine hydrochloride for the induction of emesis in cats: 47 cases (2007-2013) . J Am Vet Med Assoc . 2016 ; 248 ( 8 ): 923 - 928 . doi: 10.2460/javma.248.8.923
Thies M , Bracker K , Sinnott V . Retrospective evaluation of the effectiveness of xylazine for inducing emesis in cats: 48 cats (2011-2015) . J Vet Emerg Crit Care (San Antonio) . 2017 ; 27 ( 6 ): 658 - 661 . doi: 10.1111/vec.12641
Nystrom MR , Odunayo A , Okafor CC . Assessment of hydromorphone and dexmedetomidine for emesis induction in cats . J Vet Emerg Crit Care (San Antonio) . 2019 ; 29 ( 4 ): 360 - 365 . doi: 10.1111/vec.12866
Colby ED , McCarthy LE , Borison HL . Emetic action of xylazine on the chemoreceptor trigger zone for vomiting in cats . J Vet Pharmacol Ther . 1981 ; 4 ( 2 ): 93 - 96 . doi: 10.1111/j.1365-2885.1981.tb00716.x
Plumb DC . Hydromorphone . Plumb’s Veterinary Drugs . Accessed February 26, 2023. https://app.plumbs.com/drug-monograph/UvzrLrOaaCPROD?source=search&searchQuery=hydromorphone
Kirchofer KS , Block G , Johnson JA . Efficacy of intravenous administration of apomorphine for removal of gastric foreign material in dogs: 495 cases (2010-2015) . J Am Vet Med Assoc . 2019 ; 255 ( 4 ): 459 - 465 . doi: 10.2460/javma.255.4.459
Khan SA , McLean MK , Slater M , Hansen S , Zawistowski S . Effectiveness and adverse effects of the use of apomorphine and 3% hydrogen peroxide solution to induce emesis in dogs . J Am Vet Med Assoc . 2012 ; 241 ( 9 ): 1179 - 1184 . doi: 10.2460/javma.241.9.1179
Thawley VJ , Drobatz KJ . Assessment of dexmedetomidine and other agents for emesis induction in cats: 43 cases (2009-2014) . J Am Vet Med Assoc . 2015 ; 247 ( 12 ): 1415 - 1418 . doi: 10.2460/javma.247.12.1415
Willey JL , Julius TM , Claypool SP , Clare MC . Evaluation and comparison of xylazine hydrochloride and dexmedetomidine hydrochloride for the induction of emesis in cats: 47 cases (2007-2013) . J Am Vet Med Assoc . 2016 ; 248 ( 8 ): 923 - 928 . doi: 10.2460/javma.248.8.923
Thies M , Bracker K , Sinnott V . Retrospective evaluation of the effectiveness of xylazine for inducing emesis in cats: 48 cats (2011-2015) . J Vet Emerg Crit Care (San Antonio) . 2017 ; 27 ( 6 ): 658 - 661 . doi: 10.1111/vec.12641
Nystrom MR , Odunayo A , Okafor CC . Assessment of hydromorphone and dexmedetomidine for emesis induction in cats . J Vet Emerg Crit Care (San Antonio) . 2019 ; 29 ( 4 ): 360 - 365 . doi: 10.1111/vec.12866
Colby ED , McCarthy LE , Borison HL . Emetic action of xylazine on the chemoreceptor trigger zone for vomiting in cats . J Vet Pharmacol Ther . 1981 ; 4 ( 2 ): 93 - 96 . doi: 10.1111/j.1365-2885.1981.tb00716.x
Plumb DC . Hydromorphone . Plumb’s Veterinary Drugs . Accessed February 26, 2023. https://app.plumbs.com/drug-monograph/UvzrLrOaaCPROD?source=search&searchQuery=hydromorphone
Kirchofer KS , Block G , Johnson JA . Efficacy of intravenous administration of apomorphine for removal of gastric foreign material in dogs: 495 cases (2010-2015) . J Am Vet Med Assoc . 2019 ; 255 ( 4 ): 459 - 465 . doi: 10.2460/javma.255.4.459
Desmopressin Khan SA , McLean MK , Slater M , Hansen S , Zawistowski S . Effectiveness and adverse effects of the use of apomorphine and 3% hydrogen peroxide solution to induce emesis in dogs . J Am Vet Med Assoc . 2012 ; 241 ( 9 ): 1179 - 1184 . doi: 10.2460/javma.241.9.1179