Endoscopic evaluation of the gastroduodenal mucosa to determine the safety of short-term concurrent administration of meloxicam and dexamethasone in healthy dogs

Effects of High-Dose Prednisone on the Gastrointestinal Microbiota of Healthy Dogs

The effects of high-dose glucocorticoids on the gastrointestinal microbiota of healthy dogs are unknown. This study's aim was to investigate the effects of immunosuppressive doses of prednisone on the fecal microbiota and the gastric and duodenal mucosal microbiota in healthy dogs. Twelve healthy adult dogs were enrolled into a randomized, double-blinded, placebo-controlled trial. Dogs were evaluated on days 0, 14, and 28 following treatments with either prednisone (2 mg/kg/d) or placebo. Outcome measures included (1) composition and abundance of the fecal microbiota (via high-throughput sequencing of the 16S rRNA gene and qPCR-based dysbiosis index [DI]) and (2) spatial distribution of the gastric and duodenal mucosal microbiota using fluorescence in situ hybridization (FISH). No significant difference in alpha and beta diversity or amplicon sequence variants of the fecal microbiota was observed between treatment groups. Blautia spp. concentrations via qPCR were significantly decreased between prednisone group timepoints 2 and 3. Compared to placebo group dogs, prednisone group dogs showed significantly increased gastric mucosal helicobacters and increased mucosal-associated total bacteria and Bacteroides in duodenal biopsies over the treatment period. The results indicate that immunosuppressive dosages of prednisone alter the mucosal microbiota of healthy dogs in a time-dependent manner, which may disrupt mucosal homeostasis. This report is significant, since it addresses a knowledge gap in our understanding of the effects of glucocorticoids on the gastrointestinal mucosal microbiota of healthy dogs.

Retrospective evaluation of the incidence of gastrointestinal bleeding in dogs receiving ophthalmic nonsteroidal anti-inflammatory drugs

OBJECTIVES

To report the incidence of gastrointestinal (GI) bleeding and associated risk factors in a population of dogs receiving ophthalmic nonsteroidal anti-inflammatory drugs (NSAIDs).

ANIMAL STUDIED

Medical records of dogs prescribed ophthalmic NSAIDs (cases), dogs receiving systemic NSAIDs alone and dogs receiving systemic prednisone alone (controls).

PROCEDURES

Data were collected retrospectively from the medical records of 204 dogs prescribed ophthalmic NSAIDs (diclofenac, ketorolac, or flurbiprofen), which were subdivided based on if they received any concurrent systemic NSAIDs or glucocorticoids, 136 dogs receiving a systemic NSAID (carprofen or meloxicam) alone, and 151 dogs receiving a systemic glucocorticoid (prednisone) alone at a referral hospital from 2015 to 2019.

RESULTS

Gastrointestinal bleeds developed in 8/79 (10.1%) of topical NSAID-only cases, 10/136 (7.4%) of systemic NSAID controls, and 14/151 (9.3%) of systemic glucocorticoid controls, with no significant difference between the three groups (p = .6103). There were no significant differences in GI bleed rates between cases treated with ketorolac, diclofenac, or flurbiprofen (p = .160), although severe GI bleeding was only seen in ketorolac-treated dogs. Presence of a known concurrent risk factor for GI bleeding was significantly associated with the development of GI bleed in dogs on ophthalmic NSAIDs (p = .032).

CONCLUSIONS

Dogs treated with ophthalmic NSAIDs developed GI bleeding at a frequency comparable to dogs receiving systemic NSAIDs or systemic glucocorticoids alone, suggesting that dogs receiving ophthalmic NSAIDs may be at increased risk of GI bleeding.

Double-blinded placebo-controlled clinical trial of prophylactic omeprazole in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion

BACKGROUND

Proton pump inhibitors are administered prophylactically in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). However, their efficacy in decreasing gastrointestinal (GI) complications is unknown.

HYPOTHESIS

Omeprazole does not decrease the frequency of GI complications compared to placebo in dogs treated surgically for acute TL-IVDE.

ANIMALS

Thirty-seven client-owned dogs undergoing hemilaminectomy for acute TL-IVDE.

METHODS

Randomized double-blinded placebo-controlled prospective clinical trial. Dogs received PO placebo or omeprazole at 1 mg/kg q12h for 5 days during hospitalization. Development of GI signs (e.g., diarrhea, vomiting, regurgitation, hematochezia, melena) was recorded daily. Clinicopathologic testing performed during hospitalization and at 2 and 4-week re-evaluations included: fecal occult blood, PCV, blood urea nitrogen/creatinine ratio, fecal calprotectin, canine pancreatic lipase immunoreactivity and fecal alpha-1 proteinase inhibitor concentrations. Omeprazole and placebo groups were compared using chi-squared or Fisher's exact tests.

RESULTS

Gastrointestinal signs developed in 10/20 (50%) dogs in the omeprazole group and in 7/17 (41%) dogs in the placebo group (P = .59). Diarrhea was common (8/20 omeprazole, 5/17 placebo), hematochezia was rare (1/20 omeprazole, 1/17 placebo); melena was not observed. Clinicopathologic evidence suggestive of bleeding was present in 9/20 dogs treated with omeprazole and in 11/17 dogs that received placebo (P = .23). Fecal occult blood positivity was more common in dogs with GI signs (P = .03). Canine pancreatic lipase immunoreactivity was higher during hospitalization compared to re-evaluations (P = .01).

CONCLUSIONS AND CLINICAL IMPORTANCE

Short-term, prophylactic omeprazole treatment did not decrease clinically detectable GI complications in dogs with acute TL-IVDE.

Clinical Features and Risk Factors for Gastrointestinal Complications in Dogs Treated Surgically for Thoracolumbar Intervertebral Disc Extrusion

Gastrointestinal (GI) complications and their clinical implications are poorly characterized in dogs treated surgically for acute thoracolumbar intervertebral disc extrusion (TL-IVDE). The objective of this retrospective study was to characterize GI signs (including vomiting, diarrhea, melena, and hematochezia) in dogs undergoing hemilaminectomy for acute TL-IVDE. One-hundred and sixteen dogs were included. Frequency, type and severity of GI signs during hospitalization, duration of hospitalization and outcome were obtained from the medical record. Potential risk factors for the development of GI signs were explored using univariable and multivariable analyses. Gastrointestinal signs occurred in 55/116 dogs (47%); 22/55 dogs (40%) had one episode and 21/55 (38%) had ≥5 episodes. Diarrhea was the most common (40/55, 73%) while melena was rare (1/55, 2%). GI signs developed in 8/11 dogs (73%) treated perioperatively with both non-steroidal anti-inflammatories and corticosteroids with or without a washout period and in 25/52 dogs (48%) treated prophylactically with proton pump inhibitors. Median hospitalization was 7 days (4-15 days) vs. 5 days (4-11 days) in dogs with or without GI signs, respectively. Duration of hospitalization was associated with development of any GI signs, diarrhea and more severe GI signs (p = 0.001, 0.005, 0.021, respectively). Pre-operative paraplegia with absent pain perception was identified on univariable analysis (p = 0.005) and longer anesthetic duration on multivariable analysis to be associated with development of more severe GI signs (p = 0.047). In dogs undergoing surgery for acute TL-IVDE, GI signs were common and associated with duration of hospitalization and anesthesia. The influence of specific medications and neurologic severity on development of GI signs requires further investigation.

Medical conditions associated with gastroduodenal ulceration or erosion in 168 dogs: 2008-2018

Background

Many medical conditions are thought to cause gastroduodenal ulceration or erosion (GUE) in dogs. However, evidence for the association between many of these conditions and GUE in dogs is lacking.

Objective

To identify medical conditions associated with GUE in dogs.

Animals

One hundred and sixty‐eight dogs with GUE and 168 randomly selected control dogs without evidence of GUE identified on necropsy between January 2008 and September 2018.

Methods

Patient signalment, blood urea nitrogen (BUN) and serum creatinine concentrations, recently administered ulcerogenic drugs, as well as necropsy findings were recorded. The association between these findings and presence of GUE was assessed by univariable and multivariable analysis.

Results

In the final multivariable model, the following factors were associated with GUE: Nonsteroidal anti‐inflammatory drug (NSAID) administration (odds ratio [OR], 6.3; 95% confidence interval [CI], 2.3‐17.4; P = .0004), glucocorticoid administration (OR, 3.0; 95% CI, 1.5‐5.9; P = .001), gastrointestinal neoplasia (OR, 13.5; 95% CI, 1.7‐108.0; P = .01) and gastrointestinal mechanical disease (foreign bodies, gastric dilatation, and volvulus; OR, 4.8; 95% CI, 1.2‐19.7; P = .03). Additionally, working dog breeds were predisposed to GUE compared to mixed breed dogs (OR, 2.8; 95% CI, 1.1‐7.4; P = .04). Insufficient clinical data was available to either support or refute a role of other putative risk factors evaluated.

Conclusion and Clinical Importance

Administration of NSAID or glucocorticoid and gastrointestinal neoplasia or mechanical disease were associated with GUE in dogs. The potential predisposition of working breed dogs for GUE requires further investigation.

Antiinflammatory Drugs

This article reviews the mechanisms of action, clinical use, and recent scientific evidence for the use of nonsteroidal antiinflammatory drugs, grapiprant, acetaminophen (paracetamol), metamizole (dipyrone), and corticosteroids in pain management. The discussion is presented with an emphasis on the treatment of acute pain.

Development and implementation of a novel immune thrombocytopenia bleeding score for dogs

Background

A method of quantifying clinical bleeding in dogs with immune thrombocytopenia (ITP) is needed because ITP patients have variable bleeding tendencies that inconsistently correlate with platelet count. A scoring system will facilitate patient comparisons and allow stratification based on bleeding severity in clinical trials.

Hypothesis/Objectives

To develop and evaluate a bleeding assessment tool for dogs, and a training course for improving its consistent implementation.

Animals

Client‐owned dogs (n = 61) with platelet counts <50,000/μL; 34 classified as primary ITP, 17 as secondary ITP, and 10 as non‐ITP.

Methods

A novel bleeding assessment tool, DOGiBAT, comprising bleeding grades from 0 (none) to 2 (severe) at 9 anatomic sites, was developed. Clinicians and technicians completed a training course and quiz before scoring thrombocytopenic patients. The training course was assessed by randomizing student volunteers to take the quiz with or without prior training. A logistic regression model assessed the association between training and quiz performance. The correlation of DOGiBAT score with platelet count and outcome measures was assessed in the thrombocytopenic dogs.

Results

Clinicians and technicians consistently applied the DOGiBAT, correctly scoring all quiz cases. The odds of trained students answering correctly were higher than those of untrained students (P < .0001). In clinical cases, DOGiBAT score and platelet count were inversely correlated (r_s = −0.527, P < .0001), and DOGiBAT directly correlated with transfusion requirements (r_s = 0.512, P < .0001) and hospitalization duration (r_s = 0.35, P = .006).

Conclusions and Clinical Importance

The DOGiBAT and assessment quiz are simple tools to standardize evaluation of bleeding severity. With further validation, the DOGiBAT may provide a clinically relevant metric to characterize ITP severity and monitor response in treatment trials.

Gastroscopic Study of Meloxicam, Tramadol, and Their Combined Administration on the Development of Gastric Injuries in Dogs

Opioid and non-steroid anti-inflammatory drugs (NSAIDs) are commonly used to manage post-operative pain that may be chronically extended. Although NSAIDs have been approved for their analgesic effects in canine, they are mostly known to be associated with side effects, particularly gastric ulcers. In the present study, we evaluated short-term co-administration of meloxicam and tramadol to see if this could induce more gastric ulcers than that observed when using these drugs individually. Twenty adult mixed domestic dogs weighing 10 to 20 kg of both sexes, were randomly assigned to four groups of five dogs. In the control group, placebo was administered orally (twice a day), whereas the test groups received tramadol (per OS) twice a day, meloxicam (per OS) daily, and a combination of tramadol (twice a day) and meloxicam (daily) for ten days, respectively. The animals were evaluated for gastric injuries on days 0, 6, 11, 16 and 21 by endoscopy under general anesthesia. Clinical signs of all animals including fecal consistency, appetite, mental and hydration statuses, tempreture, heart rate and respiratory rate were evaluated daily. Based on our results, there was no significant difference between the experimental and control groups. In conclusion, our study demonstrated that a 10-day oral coadministration of tramadol and meloxicam had no deleterious effects on general health status and gastric mucosa in dogs.

Gastrointestinal Motility, Mucosal Mast Cell, and Intestinal Histology in Rats: Effect of Prednisone

Our aim was to verify the effects of prednisone related to gastrointestinal motility, intestinal histology, and mucosal mast cells in rats. Two-month-old male Wistar rats were randomly assigned to control group (vehicle) animals receiving saline 0.9% (n = 7) or treated orally with 0.625 mg/kg/day of prednisone (n = 7) or 2.5 mg/kg/day of prednisone (n = 7) during 15 days. Mast cells and other histologic analyses were performed in order to correlate to gastric emptying, cecum arrival, and small intestine transit evaluated by Alternating Current Biosusceptometry. Results showed that prednisone in adult rats increased the frequency of gastric contractions, hastened gastric emptying, slowed small intestinal transit, and reduced mucosal mast cells. Histologically, the treatment with both doses of prednisone decreased villus height, whereas longitudinal and circular muscles and crypt depth were not affected. These findings indicate an impairment of intestinal absorption which may be linked to several GI dysfunctions and symptoms. The relationship between gastrointestinal motor disorders and cellular immunity needs to be clarified in experimental studies since prednisone is one of the most prescribed glucocorticoids worldwide.

Gastroduodenal Ulceration in Small Animals: Part 1. Pathophysiology and Epidemiology

Gastroduodenal ulceration in small animals is a complex and important comorbidity that occurs when the physiological homeostasis of the gastrointestinal tract is disrupted secondary to administration of medications or the presence of local or systemic diseases. The aim of this article is to provide a comprehensive review of the veterinary literature regarding the pathophysiology, epidemiology, and risk factors associated with gastroduodenal ulceration in small animals. Pertinent concepts from the human literature will be integrated into the discussion. This article serves as an introduction to the second part of this series, which will review current evidence regarding the use of H2-receptor antagonists and proton pump inhibitors in small animals.

Gastrojejunostomy without partial gastrectomy to manage duodenal stenosis in a dog

A nine-year-old female Rottweiler with a history of repeated gastrointestinal ulcerations and three previous surgical interventions related to gastrointestinal ulceration presented with symptoms of anorexia and intermittent vomiting. Benign gastric outflow obstruction was diagnosed in the proximal duodenal area. The initial surgical plan was to perform a pylorectomy with gastroduodenostomy (Billroth I procedure), but owing to substantial scar tissue and adhesions in the area a palliative gastrojejunostomy was performed. This procedure provided a bypass for the gastric contents into the proximal jejunum via the new stoma, yet still allowed bile and pancreatic secretions to flow normally via the patent duodenum. The gastrojejunostomy technique was successful in the surgical management of this case, which involved proximal duodenal stricture in the absence of neoplasia. Regular telephonic followup over the next 12 months confirmed that the patient was doing well.

Lingual Malignant Peripheral Nerve Sheath Tumor in a Chinese Pug Dog

A 9-year-old spayed/female Chinese Pug dog presented for evaluation of a mass located on the rostral aspect of the tongue. An incisional biopsy was acquired, submitted, and interpreted as a possible granular cell tumor based on hematoxylin and eosin, and periodic acid Schiff histopathologic staining characteristics. The diagnosis was supported by immunohistochemical evaluation that was positive for S-100, vimentin, and neuron-specific enolase. Based on the absence of mitotic figures in the incisional biopsy, a partial glossectomy was performed with gross margins of at least 1-cm. The excisional biopsy revealed significant features of malignancy, with neoplastic cells in close association with peripheral nerves, consistent with malignant peripheral nerve sheath tumor. Tumor-free margins were obtained, and the glossectomy had expected healing with no recurrence apparent 6-months following surgery.

Systematic review of nonsteroidal anti-inflammatory drug-induced adverse effects in dogs

The aim of this systematic review was to identify, assess, and critically evaluate the quality of evidence of nonsteroidal anti-inflammatory drug (NSAID)-induced adverse effects in dogs. Original prospective studies published in peer-reviewed journals in English (1990-2012) that reported data on the safety of NSAIDs administration in dogs were searched. For each study, design type (I, II, III, or IV) and assessment of quality (+, Ø, -) were rated. For each drug, quantity and consistency rating (***, **, *) and strength of evidence (high, moderate, low, or extremely low) were identified and evaluated. The strength of evidence was defined in terms of how applicable and relevant the conclusions were to the target population. Sixty-four studies met the inclusion criteria. Thirty-five (55%) research studies and 29 (45%) clinical trials were identified. A high strength of evidence existed for carprofen, firocoxib, and meloxicam; moderate for deracoxib, ketoprofen, and robenacoxib; and low for etodolac. Quality and consistency rating were as follows: carprofen (***/***), deracoxib (**/***), etodolac (*/unable to rate), firocoxib (***/**), ketoprofen (**/***), meloxicam (***/***), and robenacoxib (**/**), respectively. Adverse effects were detected in 35 studies (55%) and commonly included vomiting, diarrhea, and anorexia. Three studies (5%) reported a power analysis related to adverse effects of ≥80%. In randomized, placebo-controlled, blinded studies (n = 25, 39%), the incidence of adverse effects was not statistically different between treated and control dogs. Finally, most studies were not appropriately designed to determine the safety of NSAIDs, and involved a healthy nongeriatric population of research dogs.

Efficacy of Seabuckthorn (Hippophae rhamnoides) Oil vis-a-vis Other Standard Drugs for Management of Gastric Ulceration and Erosions in Dogs

The study was conducted on 20 adult healthy medium-sized mongrel dogs. Injection of dexamethasone @ 1 mg/kg, IV, b.i.d., was administered to create gastric ulcerations and erosions. Thereafter all the animals were randomly divided into 5 equal treatment groups. Animals of groups I, II, III, IV, and V were treated with oral administration of lansoprazole @ 1.5 mg/kg, sucralfate @ 1 g/animal, misoprostol @ 10 µg/kg, famotidine @ 1 mg/kg, and Seabuckthorn seed oil @ 5 mL/animal, twice a day, respectively. Gastroendoscopically, complete healing of GUE lesions was earliest in Seabuckthorn- (SBT-) oil-treated group (7.5 ± 0.87) followed by famotidine (8.25 ± 1.44), lansoprazole (9.00 ± 1.23), misoprostol (10.50 ± 1.50), and sucralfate (13.50 ± 0.87), respectively. A marked improvement in appetite was observed in all animals. Melena was continued till day 3 in SBT group, day 6 in lansoprazole- and famotidine-treated animals, and day 9 in sucralfate and misoprostol group animals. Fecal occult blood test was positive in all animals till there was endoscopic evidence of gastric bleeding. Hematological parameters improved markedly towards the end of the study. Serum biochemical parameters remained within normal physiological limits throughout the study. It is concluded that Seabuckthorn oil was the best therapeutic agent for dexamethasone-induced GUE in dogs followed by famotidine, lansoprazole, misoprostol, and sucralfate.

Update on immununosuppressive therapies for dogs and cats

Treatment of immune-mediated disease in dogs and cats continues to evolve as new therapies are introduced or adapted from human medicine. Glucocorticoids remain the first-line therapy for many of the immune-mediated or inflammatory diseases of cats and dogs. The focus of this article is to provide an update on some of the common immunosuppressive therapies used in small animal veterinary medicine. The goals of therapy are to induce disease remission through the inhibition of inflammation and the modulation of lymphocyte function.

Clinical pharmacology of nonsteroidal anti-inflammatory drugs in dogs

OBJECTIVES

To discuss the clinical pharmacology of currently licensed veterinary NSAIDs and to review gastrointestinal and renal adverse effects as well as drug-drug interactions that have been reported with these drugs. To review the use of NSAIDs in the peri-operative setting and their use in patients with osteoarthritis. To further review the reported effects of NSAIDs on canine articular cartilage and liver as well as the clinical relevance of a washout period.

DATABASES USED

PubMed, CAB abstracts and Google Scholar using dog, dogs, nonsteroidal anti-inflammatory drugs and NSAID(s) as keywords.

CONCLUSIONS

A good understanding of the mechanisms by which NSAIDs elicit their analgesic effect is essential in order to minimize adverse effects and drug-drug interactions. Cyclooxygenase (COX) is present in at least two active isoforms in the body and is the primary pharmacologic target of NSAIDs. Inhibition of COX is associated with the analgesic effects of NSAIDs. COX is present in the gastrointestinal tract and kidneys, along with other areas of the body, and is also the likely reason for many adverse effects including gastrointestinal and renal adverse effects. The newer veterinary approved NSAIDs have a lower frequency of gastrointestinal adverse effects in dogs compared to drugs such as aspirin, ketoprofen and flunixin, which may be due to differential effects on the COX isoforms. There are currently no published reports demonstrating that the newer NSAIDs are associated with fewer renal or hepatic adverse effects in dogs. NSAIDs remain the cornerstone of oral therapy for osteoarthritis unless contraindicated by intolerance, concurrent therapies or underlying medical conditions. NSAIDs are also effective and frequently used for the management of post-operative pain.

Effects of zinc-L-carnosine and vitamin E on aspirin-induced gastroduodenal injury in dogs

BACKGROUND

Nonsteroidal anti-inflammatory drugs frequently cause gastrointestinal (GI) injury. Zinc-L-carnosine has antioxidant, anti-inflammatory, mucosal protective, and healing properties in rodent models and in some human studies of GI injury.

HYPOTHESIS

The combination of zinc-L-carnosine and vitamin E attenuates aspirin-induced gastroduodenal mucosal injury.

ANIMALS

Eighteen healthy random-source Foxhound dogs.

METHODS

In this randomized, double-blinded, placebo-controlled study dogs were treated with placebo (n = 6; 0X group), 30 mg/30 IU (n = 6; 1X group), or 60 mg/60 IU (n = 6; 2X group) zinc-L-carnosine/vitamin E orally every 12 hours for 35 days. Between Day 7 and 35, GI mucosal lesions were induced with aspirin (25 mg/kg p.o. q8h). Mucosal injury lesions (hemorrhage, erosion, and ulcer) were assessed by gastroduodenoscopy on Days 14, 21, and 35 with a 12-point scoring scale.

RESULTS

At baseline (Day -1) gastroscopy scores were not significantly different between groups (mean ± SD: 0X, 4.4 ± 0.8; group 1X, 4.4 ± 0.6; group 2X, 4.2 ± 0.3; P= .55). Gastroscopy scores increased significantly in all groups between Day -1 and Days 14, 21, and 35 (P < .0001). On Day 35, gastroscopy scores were 29.2 ± 5.2 (0X), 27.3 ± 3.7 (1X), and 28.6 ± 3.3 (2X). Mean gastroscopy scores were not significantly different among treatment groups on any of the days (P = .61).

CONCLUSIONS AND CLINICAL IMPORTANCE

Administration of the combination of zinc-L-carnosine and vitamin E at 1X or 2X dosing did not attenuate aspirin-induced gastroduodenal mucosal injury.

Spontaneous gastroduodenal perforations in dogs: a retrospective study of 15 cases

The clinical findings and outcomes following surgical management of spontaneous gastroduodenal perforations in 15 dogs were reviewed in a retrospective study to identify related risk factors. Clinical and clinicopathological findings were diverse. Use of multiple diagnostic procedures yielded a strong index of suspicion for gastrointestinal perforation. There was a trend towards improved survival for animals with perforation of the gastric fundus/body compared to pyloric or duodenal perforation, although the difference was not statistically significant. Five dogs were euthanased at surgery; two dogs died within two days after surgery. Seven of the eight surviving dogs had a favourable long-term outcome. Previous administration of NSAIDs was the only identified predisposing factor in ten of 10 of the dogs.

Effects of prednisone alone or prednisone with ultralow-dose aspirin on the gastroduodenal mucosa of healthy dogs

BACKGROUND

The coadministration of prednisone and ultralow-dose aspirin has been recommended for the management of various diseases, but the safety of this combination in dogs has not been studied.

HYPOTHESES

The gastroduodenal lesions associated with prednisone and ultralow-dose aspirin administration will be similar to those caused by prednisone alone, but both treatments will result in more severe lesions than placebo.

ANIMALS

Eighteen healthy adult purpose-bred dogs.

METHODS

Randomized, blinded, placebo-controlled study of 3 treatment groups for 27 days: placebo, prednisone, and prednisone and aspirin. Gastroduodenoscopy was performed before and on days 5, 14, and 27 of treatment and mucosal lesions scores were assigned. Mucosal lesion scores were compared by a Kruskal-Wallis test. Clinical signs were compared by the Friedman's chi-square test (significance at P < .05).

RESULTS

There were no significant differences in the gastroduodenal lesion scores among groups, or within groups at any time during the study. Significantly more dog-days of diarrhea occurred in the prednisone and aspirin group during treatment, compared with baseline. No significant differences in clinical signs were found among any of the groups.

CONCLUSION

The concurrent use of prednisone and ultralow-dose aspirin did not increase the severity of gastroduodenal lesions compared with prednisone or placebo. Coadministration of prednisone and ultralow-dose aspirin increases the frequency of mild, self-limiting diarrhea in some dogs.

Evaluation of the adverse effects of oral firocoxib in healthy dogs

This study evaluated the adverse effects of oral firocoxib in dogs. Six dogs (20.2+/-6.3 kg) were studied. Values for complete blood count (CBC), serum urea, creatinine, alanine transaminase, alanine phosphatase, gamma-glutamyl transferase, occult blood in feces, platelet aggregation, and buccal mucosal bleeding time were measured before and 7, 14, 21, and 29 days after SID treatment with firocoxib 5.3+/-0.34 mg/kg (FG) or lactose 1 mg/kg (LG) for 28 days, in a randomized crossover study. Gastrointestinal (GI) tract endoscopy was performed before treatment began and at 29 days. Lesions were scored from grade 0 to 6. Data were analyzed using anova and paired t-tests (P<0.05). None of the dogs presented adverse clinical effects. There were no significant changes in CBC, biochemical profiles within groups, or differences between groups. Pretreatment mean+/-SD bleeding time (LG, 70.7+/-32.1 sec; FG, 75.8+/-38.1 sec) and platelet aggregation (LG, 86.4+/-10.2%; FG, 85.6+/-9.2%) were not significantly different from readings at 29 days (LG, 95.2+/-25 sec; FG, 91.7+/-24 sec and LG, 73.2+/-15.1%; FG, 84+/-10.3%) nor the groups were different. None of the dogs had positive fecal occult blood tests, and endoscopic lesion scores were grade 0 both before treatment and at 29 days. Administration of firocoxib did not cause any adverse effects on GI, or hematological or serum biochemical variables and appears to have been well tolerated by dogs.

Evaluation of adverse effects of long-term oral administration of carprofen, etodolac, flunixin meglumine, ketoprofen, and meloxicam in dogs

OBJECTIVE

To evaluate adverse effects of long-term oral administration of carprofen, etodolac, flunixin meglumine, ketoprofen, and meloxicam in dogs.

ANIMALS

36 adult dogs.

PROCEDURES

Values for CBC, urinalysis, serum biochemical urinalyses, and occult blood in feces were investigated before and 7, 30, 60, and 90 days after daily oral administration (n = 6 dogs/group) of lactose (1 mg/kg, control treatment), etodolac (15 mg/kg), meloxicam (0.1 mg/kg), carprofen (4 mg/kg), and ketoprofen (2 mg/kg for 4 days, followed by 1 mg/kg daily thereafter) or flunixin (1 mg/kg for 3 days, with 4-day intervals). Gastroscopy was performed before and after the end of treatment.

RESULTS

For serum gamma-glutamyltransferase activity, values were significantly increased at day 30 in dogs treated with lactose, etodolac, and meloxicam within groups. Bleeding time was significantly increased in dogs treated with carprofen at 30 and 90 days, compared with baseline. At 7 days, bleeding time was significantly longer in dogs treated with meloxicam, ketoprofen, and flunixin, compared with control dogs. Clotting time increased significantly in all groups except those treated with etodolac. At day 90, clotting time was significantly shorter in flunixin-treated dogs, compared with lactose-treated dogs. Gastric lesions were detected in all dogs treated with etodolac, ketoprofen, and flunixin, and 1 of 6 treated with carprofen.

CONCLUSIONS AND CLINICAL RELEVANCE

Carprofen induced the lowest frequency of gastrointestinal adverse effects, followed by meloxicam. Monitoring for adverse effects should be considered when nonsteroidal anti-inflammatory drugs are used to treat dogs with chronic pain.

Nonsteroidal anti-inflammatory drugs in cats: a review

OBJECTIVE

To review the evidence regarding the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in cats.

DATABASES USED

PubMed, CAB abstracts.

CONCLUSIONS

Nonsteroidal anti-inflammatory drugs should be used with caution in cats because of their low capacity for hepatic glucuronidation, which is the major mechanism of metabolism and excretion for this category of drugs. However, the evidence presented supports the short-term use of carprofen, flunixin, ketoprofen, meloxicam and tolfenamic acid as analgesics in cats. There were no data to support the safe chronic use of NSAIDs in cats.

Effect of short-term sequential administration of nonsteroidal anti-inflammatory drugs on the stomach and proximal portion of the duodenum in healthy dogs

OBJECTIVE

To evaluate effects of injection with a nonsteroidal anti-inflammatory drug (NSAID) followed by oral administration of an NSAID on the gastrointestinal tract (GIT) of healthy dogs.

ANIMALS

6 healthy Walker Hounds.

PROCEDURES

In a randomized, crossover design, dogs were administered 4 treatments consisting of an SC injection of an NSAID or control solution (day 0), followed by oral administration of an NSAID or inert substance for 4 days (days 1 through 4). Treatment regimens included carprofen (4 mg/kg) followed by inert substance; saline (0.9% NaCl) solution followed by deracoxib (4 mg/kg); carprofen (4 mg/kg) followed by carprofen (4 mg/kg); and carprofen (4 mg/kg) followed by deracoxib (4 mg/kg). Hematologic, serum biochemical, and fecal evaluations were conducted weekly, and clinical scores were obtained daily. Endoscopy of the GIT was performed before and on days 1, 2, and 5 for each treatment. Lesions were scored by use of a 6-point scale.

RESULTS

No significant differences existed for clinical data, clinicopathologic data, or lesion scores in the esophagus, cardia, or duodenum. For the gastric fundus, antrum, and lesser curvature, an effect of time was observed for all treatments, with lesions worsening from before to day 2 of treatments but improving by day 5.

CONCLUSIONS AND CLINICAL RELEVANCE

Sequential administration of NSAIDs in this experiment did not result in clinically important gastroduodenal ulcers. A larger study to investigate the effect of sequential administration of NSAIDs for longer durations and in dogs with signs of acute and chronic pain is essential to substantiate these findings.

The Interaction between Orally Administered Non-Steroidal Anti-Inflammatory Drugs and Prednisolone in Healthy Dogs

The interaction between oral non-steroidal anti-inflammatory drugs (NSAIDs) and prednisolone administered concurrently for 30 days was studied in 18 healthy dogs divided into 3 groups of 6 dogs each: a drug-free negative control group (NC group) given 2 gelatin capsules; a group given meloxicam (0.1 mg/kg) and prednisolone (0.5 mg/kg) (MP group); and a group given a reduced dosage of ketoprofen (0.25 mg/kg, p.o.) and prednisolone (0.5 mg/kg, p.o.) (KP group). The dogs were periodically monitored by physical examinations, blood analyses, endoscopic examinations, fecal occult blood tests, renal function tests [effective renal plasma flow (ERPF) and glomerular filtration rate (GFR)], urinalyses [urinary sediments, and urinary micro-albumin to creatinine ratio (UAlb/Cre)], urinary enzyme indices, and haemostatic function tests [buccal mucosa bleeding time (BMBT), cuticle bleeding time (CBT)]. Significant changes were observed in the KP group, including a decrease of ERPF and GFR, an increased UAlb/Cre ratio, prolonged BMBT and CBT, as well as the presence of more severe grades of endoscopic lesions and fecal occult blood. In both the MP and KP groups, abnormal enzymuria with exfoliation of renal tubular epithelial cells in the urine was found. However, no significant changes in any of the other tests were observed in the MP group compared with the NC group. These findings suggest that the combination of NSAIDs, even selective COX-2 inhibitors, with prednisolone may be contraindicated due to the potential for serious adverse effects on the kidneys, the platelets, and the gastrointestinal tract.

The Clinical Pharmacology of Cyclooxygenase-2–Selective and Dual Inhibitors

Over the past decade, there have been several nonsteroidal anti-inflammatory drugs (NSAIDS) introduced in veterinary medicine with an increased gastrointestinal safety profile consistent with a cyclooxygenase (COX)-1-sparing effect. More recently, an NSAID with additional 5-lipoxygenase (5-LOX) activity has also been approved for use. Although it is tempting to equate in vitro COX-2/COX-1 and 5-LOX inhibition to overall in vivo safety, the data do not support this approach. The true overall safety for any individual compound is based on its evaluation in laboratory margin-of-safety studies, reproductive safety studies, and blind multicenter field studies in client-owned animals. Therefore, when choosing a COX-2-selective or dual-inhibitor NSAID for clinical use, all in vivo data must be taken into account to understand comparative safety, and continued use must be based on the drug's performance in the individual being treated. Until head-to-head trials in multicenter blind studies are published, comments on comparative safety and effectiveness must be reserved.

Gastrointestinal tract perforation in dogs treated with a selective cyclooxygenase-2 inhibitor: 29 cases (2002-2003)

OBJECTIVE

To identify factors associated with gastrointestinal tract perforation in dogs being treated with a selective cyclooxygenase-2 (COX-2) inhibitor (deracoxib).

DESIGN

Retrospective study.

ANIMALS

29 dogs.

PROCEDURE

The Novartis Animal Health pharmacovigilance database was searched for records of dogs treated with deracoxib in which gastrointestinal tract perforation was documented. Results-16 of the 29 (55%) dogs had received deracoxib at a dosage higher than that approved by the FDA for the particular indication being treated, with 25 (86%) dogs having received deracoxib at a dosage > 2 mg/kg/d (0.9 mg/lb/d). Seventeen (59%) dogs had received at least 1 other nonsteroidal anti-inflammatory drug (NSAID) or a corticosteroid in close temporal association (within 24 hours) with deracoxib administration (ie, immediately before or following). In all, 26 (90%) dogs had received deracoxib at a higher-than-approved dosage or had received at least 1 other NSAID or corticosteroid in close temporal association with deracoxib administration. Twenty dogs died or were euthanatized, and 9 survived.

CONCLUSIONS AND CLINICAL RELEVANCE

In dogs with gastrointestinal tract perforation and that had been treated with deracoxib, perforation was most likely attributable to a number of factors. Deracoxib should only be used at approved dosages. Cortico-steroids and other less selective NSAIDs should not be administered in close temporal association with selective COX-2 inhibitors, including deracoxib. Further study is required to define this problem.