Use of anti-inflammatory and analgesic drugs in dogs and cats

SUMMARY: Responses (486) were collated from a survey of 5054 Australian veterinarians on their use of anti-inflammatory and analgesic drugs in dogs and cats. Almost all respondents used glucocorticoids (usually prednisolone) to treat allergic, pruritic dermatoses in dogs, while two-thirds also gave fatty acid supplements and one-half used antihistamines. Almost 60% of respondents initially injected a glucocorticoid (frequently a long-acting preparation) when treating inflammatory skin diseases in dogs. More than 90% of respondents used glucocorticoids to treat immunemediated haemolytic anaemia or thrombocytopenia, and about one-third also gave cytotoxic drugs. Administration of prednisolone on alternate days was generally favoured for long-term enteral steroid therapy. Phenylbutazone was the most preferred treatment for painful or inflammatory musculoskeletal disorders of dogs, but aspirin and pentosan polysulphate were also used widely. Regarding the use of analgesics drugs generally, both narcotic analgesics and non-steroidal anti-inflammatory drugs (NSAIDs) were used more widely in dogs than in cats, but alpha-2 agonists were used similarly in both species. The most commonly used narcotic analgesics were pethidine and buprenorphine in both species, while the NSAIDs used most often were flunixin and dipyrone in dogs and ketoprofen in cats. More than 80% of respondents generally used analgesic drugs with potentially painful surgical procedures, with doses given usually before anaesthetic recovery. Analgesic use rates varied with the condition, ranging from 94% for patients with acute severe trauma, through 60% for cruciate ligament repair and 29% for perineal herniorrhaphy, to about 5% for ovariohysterectomy and dog castration. The three clinical signs most frequently nominated as indicators of pain in dogs and cats were (in descending order) vocalisation, response to handling or palpating the affected area, and mental depression. Other items mentioned frequently were behavioural changes and immobility (in both species), inappetence/anorexia in cats, and altered respiration in dogs.     

Long-term treatment of dogs with steroid-responsive meningitis-arteritis: clinical, laboratory and therapeutic results

Steroid-responsive meningitis-arteritis is an immunopathological disease in dogs characterised by neck pain, pleocytosis of the cerebrospinal fluid (CSF) and increased serum and CSF immunoglobulin (Ig) A levels. A long-term treatment protocol (four to 20 months) with prednisolone was applied in 10 dogs with the condition. Clinical side effects, changes in blood and CSF values and long-term outcome were evaluated retrospectively. Eight of the 10 dogs were without clinical signs up to 29 months after the treatment was terminated. Long-term glucocorticosteroid treatment appears to result only in mild clinical side effects, such as polyuria/polydipsia, polyphagia and weight gain. All clinical and laboratory changes were reversible after the therapy was discontinued. Elevated serum and CSF IgA levels did not decrease to normal values during prednisolone treatment and were still slightly increased after the therapy was discontinued. A marked decrease in the cell count of the CSF was observed after therapy was initiated, although pleocytosis increased again during relapses of the disease. Monitoring of CSF cell count in dogs with this condition seems to be a sensitive indicator of success of treatment. In addition, older dogs with high IgA levels in the CSF and frequent relapses seem to require a longer duration of therapy and have a less favourable prognosis long term. The reason for high systemic and intrathecally produced IgA levels remains unknown, but seems not to be influenced by prednisolone treatment.     

Benzocaine-induced methemoglobinemia in dogs

Methemoglobinemia developed in three dogs after the owners' use of benzocaine-containing products for topical treatment of the dogs' pruritic skin conditions. The products were intended for use in man. In two of the dogs, clinical signs of shock were observed within a few hours after the application of a skin lotion containing 5% benzocaine. Methemoglobin was assayed in one case and found to be 51% of total hemoglobin. Both dogs recovered after whole blood transfusions were given. The third dog, which had been treated for several weeks with small amounts of an anesthetic aerosol containing 20% benzocaine, was anorectic and lethargic when examined. Methemoglobin content was 30%, and Heinz bodies were observed in 20% of the erythrocytes. The methemoglobin content and proportion of Heinz bodies decreased rapidly after use of the spray was discontinued. The two benzocaine-containing products incriminated in development of the methemoglobinemia did not induce measurable increases in methemoglobin content in clinically normal dogs, when applied to unbroken skin. Small increases in methemoglobin content were measured, however, when these products were given orally to clinically normal dogs. It was concluded that the skin lesions in the three clinically affected dogs enhanced absorption of the drug, resulting in methemoglobin formation.     

Double-blinded, placebo-controlled study to evaluate an antipruritic shampoo for dogs with allergic pruritus

Shampoo therapy is frequently used on pruritic dogs. However, there are few double-blinded, placebo-controlled studies of this form of therapy. This randomised, double-blinded, placebo-controlled study evaluated the efficacy of a commercial medicated shampoo (DermaTopic; Almapharm) containing chlorhexidine, lactoferrin, piroctone olamine, chitosan and essential fatty acids in 27 dogs with mild to moderate allergic pruritus without secondary skin infections. All dogs received shampoo therapy with either DermaTopic or a shampoo vehicle as placebo twice weekly for four weeks. The extent of pruritus was evaluated before the study and then on a daily basis by the owners using a visual analogue scale. Before beginning the treatment and after four weeks, the skin lesions were evaluated by an experienced clinician with a validated lesion score (Canine Atopic Dermatitis Extent and Severity Index - CADESI). The pruritus was reduced significantly by both DermaTopic and placebo. However, there was no significant difference between both groups. There was no statistically significant difference in the CADESI scores pre- and post-treatment in either group or between the two types of treatment. This study provides further evidence of the benefit of shampoo therapy for pruritic dogs.     

Fat absorption in dogs with demodicosis or zinc-responsive dermatosis.

Quantitative absorption of long-chain triglycerides was studied in normal dogs, dogs with demodicosis and dogs which had been successfully treated for zinc-responsive dermatosis. The mean serum triglyceride concentration of dogs treated for zinc-responsive dermatosis was significantly lower than that of normal dogs before (P less than 0.01) and at one hour (P less than 0.01) and two, three and four hours (P less than 0.001) after feeding vegetable oil. No significant difference was detected in the mean serum triglyceride concentration of dogs with demodicosis and normal dogs at any of the sampling times.     

Effect of oral administration of prednisolone on thyroid function in dogs

To determine the effect of oral administration of prednisolone on thyroid function, 12 healthy Beagles were given 1.1 mg of prednisolone/kg of body weight every 12 hours for 22 days after 8 days of diagnostic testing of the dogs before treatment with prednisolone. Thyroid-stimulating hormone (TSH) and thyrotropin-releasing hormone (TRH) response tests were performed before treatment (days 1 and 8 of the study) and during treatment (days 21 and 28 of the study). Blood samples were collected daily at 8 AM and 2 and 8 PM to rule out normal daily hormone fluctuations as the cause of a potential decrease in serum triiodothyronine (T3), thyroxine (T4), and free T4 (fT4) concentrations. Serum T3, T4, and fT4 concentrations before treatment and 1 day and 21 days after the first prednisolone dose were compared by analyses of variance. Post-TSH and -TRH serum T3 and T4 concentrations before and during treatment were compared, using the Student t test for paired data. Oral administration of prednisolone significantly (P less than 0.005) decreased serum T3, T4, and fT4 concentrations in the 8 AM and 2 and 8 PM samples obtained 1 day and 21 days after the first prednisolone dose. Serum T4 and fT4 concentrations in 8 AM and 2 PM samples were significantly (P less than 0.05) lower 21 days after the first prednisolone dose than they were at 1 day after the first dose. Before treatment, serum T4 concentration in the 2 PM samples was significantly (P less than 0.05) higher than serum T4 concentration in 8 AM and 8 PM samples.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pseudogout in two dogs

Extract

Pseudogout is a common condition in elderly people in which sudden onset of intense joint pain and synovitis develop. Peri-synovial calcium crystal deposition is the cause of the synovitis rather than the uric acid deposition in common gout. It is a rare condition in dogs, having only been reported twice before. Two dogs presenting with acute lameness and pyrexia showed many macrophages and occasional neutrophils containing intracellular crystals on cytological examination of synovial fluid. The crystals were single or multiple, small to large, clear, square or rhomboid-shaped, weakly birefringent and resembled those described for pseudogout. Occasional crystals were also present free in the matrix. Non-steroidal anti-inflammatory drugs that are effective in reducing pain in people with pseudogout provided no relief to either patient, but twice daily oral prednisolone therapy was successful. Dosage was gradually tapered as clinical signs improved over a period of 6 weeks.     

Effect of alternate-day prednisolone administration on hypophyseal-adrenocortical activity in dogs.

OBJECTIVE: To evaluate effect of alternate-day oral administration of prednisolone on endogenous plasma ACTH concentration and adrenocortical response to exogenous ACTH in dogs. ANIMALS: 12 Beagles. PROCEDURE: Dogs were allotted to 2 groups (group 1, 8 dogs treated with 1 mg of prednisolone/kg of body weight; group 2, 4 dogs given excipient only). During a 30-day period, blood samples were collected for determination of plasma ACTH and cortisol concentrations before, during, and after treatment with prednisolone. From day 7 to 23, prednisolone or excipient was given on alternate days. Sample collection (48-hour period with 6-hour intervals) was performed on days 1, 7, 15, 21, and 28; on other days, sample collection was performed at 24-hour intervals. Pre- and post-ACTH plasma cortisol concentrations were determined on days 3, 9, 17, 23, and 30. RESULTS: A significant difference was detected between treatment and time for group 1. Plasma ACTH concentrations significantly decreased for 18 to 24 hours after prednisolone treatment in group-1 dogs. At 24 to 48 hours, ACTH concentrations were numerically higher but not significantly different in group-1 dogs. Post-ACTH plasma cortisol concentration significantly decreased after 1 dose of prednisolone and became more profound during the treatment period. However, post-ACTH cortisol concentration returned to the reference range 1 week after prednisolone administration was discontinued. CONCLUSIONS AND CLINICAL RELEVANCE: Single oral administration of 1 mg of prednisolone/kg significantly suppressed plasma ACTH concentration in dogs for 18 to 24 hours after treatment. Alternate-day treatment did not prevent suppression, as documented by the response to ACTH.     

Successful management of histiocytic ulcerative colitis with enrofloxacin in two Boxer dogs

Two Boxer dogs with histologically confirmed histiocytic ulcerative colitis were treated with enrofloxacin, one as sole therapy and one in conjunction with prednisolone, after failure of standard therapy. Clinical remission occurred rapidly in both dogs after commencement of enrofloxacin and in one case where repeat colonoscopy was performed the endoscopic appearance of the mucosa was normal within 2 weeks. Histological examination of the colonic mucosa in this dog after 7 months showed resolution of the cellular infiltration characteristic of histiocytic ulcerative colitis. Histological improvement following therapy in Boxer dogs with histiocytic ulcerative colitis has not been reported previously.     

An aspirin-prednisolone combination to modify postadulticide lung disease in heartworm-infected dogs

A combination of aspirin and prednisolone was used in an attempt to modify the pulmonary disease produced by thiacetarsamide treatment of heartworm-infected dogs. Results of 6 heartworm-infected dogs treated with prednisolone (1 mg/kg, daily for 4 weeks) and aspirin (10 mg/kg, daily for 4 weeks) after thiacetarsamide treatment were compared with previously published results of 3 groups of dogs (6 dogs/group). One of these 3 groups was a nontreated control group, another was treated with prednisolone, and the 3rd was treated with aspirin. All dogs, each with 9 adult heartworms transplanted, were treated with a 2-day, twice-a-day treatment of thiacetarsamide (1 mg/kg) 4 weeks after the transplant. Thoracic radiographs were taken before and at 1, 2, and 3 weeks after thiacetarsamide treatment to evaluate lung disease. Pulmonary arteriography was performed before and 3.5 weeks after thiacetarsamide treatment to evaluate pulmonary blood flow. After treatment, radiographs of the aspirin-prednisolone group were similar to radiographs of the prednisolone group, both with a marked attenuation of the parenchymal disease, as compared with the non-treated group. Addition of aspirin to prednisolone prevented the blood flow obstruction and intraluminal filling defects that were present in the groups not receiving aspirin. Sixteen of 54 transplanted heartworms survived thiacetarsamide treatment in both prednisolone-treated groups, in contrast to complete elimination of heartworms in the nontreated group. Aspirin may be considered for treatment of any heartworm-infected dog that does not have hemotypsis, but postthiacetarsamide use of prednisolone should be restricted to the dog that develops severe lung disease after the heartworms have been killed.     

Cyclosporine decreases skin lesions and pruritus in dogs with atopic dermatitis: a blinded randomized prednisolone-controlled trial

During the last decade, oral cyclosporin (CsA) has proven to be effective, in randomized controlled trials, for the treatment of atopic dermatitis (AD) in human patients. The purpose of this blinded randomized controlled trial was to test the hypothesis that CsA was successful in reducing the gravity of clinical signs of AD in dogs. Thirty dogs with nonseasonal AD were randomly allocated to receive an oral solution of either NEORAL CsA (5 mg kg-1) or prednisolone (0.5 mg kg-1) once daily for 6 weeks. Before, and 3 and 6 weeks after therapy, skin lesions were graded by clinicians using the Canine AD Extent and Severity Index (CADESI). Pruritus was assessed by the owners using a visual analog scale (PVAS). In both groups, CADESI and PVAS values were significantly lower at 6 weeks post treatment than before the initiation of therapy (Friedman test, P < 0.0004). The percentage reductions in CADESI and PVAS values from baseline were not statistically different between groups (Mann-Whitney test, P > 0.3). In this experiment, the tolerability and safety of oral CsA and prednisolone appeared similar. One-fifth of dogs given oral CsA occasionally developed diarrhoea or soft stools. One dog that was given CsA developed a generalized papillomatous skin eruption during the second half of the trial. Our study provides randomized controlled trial evidence that CsA reduces the severity of clinical signs in dogs with nonseasonal AD. Moreover, the anti-allergic efficacy of CsA appears comparable with that of prednisolone. We propose that oral CsA should be considered as a valuable alternative to glucocorticoid therapy in dogs with AD.     

Pemphigus foliaceus in 91 dogs

A retrospective study of 91 dogs with pemphigus foliaceus was performed. Clinical signs of the disease included crusts (n=79), pustules (n=36), and alopecia (n=33). Lesions were most common on the trunk (n=53), inner pinnae (n=46), face (n=37), and foot pads (n=32). Cytological evaluation revealed acantholytic keratinocytes in 37 of 48 dogs. Results of combination treatment with prednisolone and azathioprine were comparable to results with prednisolone therapy alone. More than half of the dogs achieved remission with appropriate therapy, and another 25% significantly improved.     

Multiple-center study of reduced-concentration triamcinolone topical solution for the treatment of dogs with known or suspected allergic pruritus

OBJECTIVE: To determine the efficacy of triamcinolone acetonide topical solution (TTS) in dogs for use in reduction of clinical signs of pruritic inflammatory skin diseases of a known or suspected allergic basis and to evaluate adverse effects associated with TTS administration. ANIMALS: 103 pruritic adult dogs with known or suspected allergic skin disease. PROCEDURE: Dogs were treated for 4 weeks with TTS or with vehicle solution (control dogs) in a multiple-center study. Clinical signs were scored by owners and by examining veterinarians before and after treatment. Blood samples obtained before and after treatment were subjected to routine hematologic and serum biochemical analyses. RESULTS: Treatment success, as defined by an improvement of at least 2 of 6 grades in overall clinical score, was evident in 35 of 52 (67%) TTS-treated dogs (mean improvement, 1.98) and 12 of 51 (24%) control dogs (mean improvement, 0.29). For several criteria, TTS was significantly more effective than vehicle in reducing clinical signs. Minor alterations in hematologic determinations in TTS-treated dogs were limited to slightly lower total leukocyte, lymphocyte, and eosinophil counts after treatment. Minor adverse effects were reported by owners in 6 of 52 (12%) TTS-treated and 9 of 51 (18%) control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Triamcinolone used as a spray solution at a concentration approximately one-sixth the concentration of triamcinolone topical preparations currently available for veterinary use is effective for short-term alleviation of allergic pruritus in dogs. Adverse effects are few and mild and, thus, do not preclude prolonged treatment with the solution.     

Uric acid and phosphorus excretion in dogs with lymphosarcoma

Serum uric acid and phosphorus concentrations were determined for 27 dogs with multicentric lymphosarcoma before and after chemotherapy. Mean serum uric acid values in dogs before treatment were significantly higher (P less than 0.05) than those of a control group of healthy dogs. Serum uric acid values did not change after treatment. Of the 27 dogs, 13 had 24-hour urine collections to determine endogenous creatinine clearance and quantitation of uric acid and phosphorus excretion before and after treatment for lymphosarcoma. Mean values for 24-hour creatinine clearance before and after treatment were statistically similar in dogs with lymphosarcoma, although the values were lower than those in a normal range. Total urinary phosphorus excretions were increased significantly (P less than 0.01) after treatment without change in fractional excretion. Chemotherapeutic agents used accounted for the significant (P less than 0.05) increase in urine volume after treatment and may have affected the excretion of uric acid and phosphorus. Seemingly, dogs with uncomplicated lymphosarcoma rarely have renal dysfunction or clinically important alterations in uric acid or phosphorus excretion secondary to rapid tumor lysis. However, preexisting renal disease or systemic complications, such as hypercalcemia, may be associated with increased risk of further renal impairment during treatment.     

Pharmacokinetics of prednisolone sodium succinate and its metabolites in normovolemic and hypovolemic dogs

Tritium-labeled prednisolone sodium succinate was administered IV to 4 healthy, awake, nonsplenectomized dogs. The concentration of prednisolone and its metabolites in the plasma were measured for 10 hours. Forty-one percent of the blood volume of these dogs was removed, and plasma prednisolone was measured again. The data before and after hemorrhage were fitted to a 2-compartment open model. From plasma profiles, a rapid distributional phase, followed by a slower phase, was observed in control and shock groups. Volume of the central compartment of prednisolone before and after hemorrhage was 165 ml/kg of body weight and 110 ml/kg, respectively; and the difference was significant (P less than 0.05). The rate of total body clearance of prednisolone before and after hemorrhage was 3.96 ml/min/kg and 2.53 ml/min/kg, respectively; the difference was significant. The mean plasma half-lives for prednisolone sodium succinate and its metabolites, before and after hemorrhage, were 166 and 197 minutes, respectively; the difference was not significant. The mean half-life data indicated that prednisolone sodium succinate may be repeated in a patient 2.5 to 3 hours after onset of treatment if signs of hypovolemic shock reappear.     

Prednisolone therapy for atopic dermatitis is less effective in dogs with lower pretreatment serum 25-hydroxyvitamin D concentrations

Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured in 20 dogs with atopic dermatitis prior to treatment with a standard therapeutic dosage of prednisolone (0.93-1.06 mg/kg) every other day for 5 weeks after 7 days of treatment with the same dosage once daily. The severity of their physical signs was scored before and 6 weeks after prednisolone treatment by the canine atopic dermatitis extent and severity index version 3 (CADESI-03) and the Edinburgh Pruritus Scale (EPS). The 20 dogs with atopic dermatitis that were treated with prednisolone did not have significantly lower serum concentrations of 25(OH)D than a group of 36 healthy dogs, and the physical severity of the atopic dermatitis was not correlated to pretreatment serum 25(OH)D concentrations. However, dogs which had a marked improvement of their physical signs, defined by a post-treatment EPS score of 0 and/or an 85% reduction in CADESI-03 score, had significantly higher pretreatment serum 25(OH)D concentrations than dogs with a suboptimal response (P = 0.003 and P = 0.03, respectively). Serum 25(OH)D concentrations were also measured in a previously published cohort of atopic dogs that were treated with ciclosporin. This cohort of dogs was recruited in a similar time frame to the prednisolone-treated dogs, and all samples were handled in the same way. In contrast to the prednisolone-treated dogs, there was no significant difference in 25(OH)D concentrations in dogs that responded optimally to ciclosporin compared with suboptimal responders. Additional studies are required to establish whether vitamin D has a synergistic therapeutic effect with prednisolone in dogs with atopic dermatitis.     

Prednisolone is associated with an increase in serum insulin but not serum fructosamine concentrations in dogs with atopic dermatitis

The aim of this study was to assess the effects of a standard therapeutic protocol of prednisolone (Pred) on glucose homeostasis in atopic dogs and compare it with previously published data for ciclosporin A (CsA). The central aim of the study was to assess and compare the effects of standard therapeutic protocols of prednisolone (Pred) and ciclosporin A (CsA) on glucose homeostasis in dogs with atopic dermatitis (CAD). Both treatments significantly reduced the physical signs of CAD, as determined by the canine atopic dermatitis extent and severity index version 3 (CADESI-03) and the Edinburgh Pruritus Scale (EPS). Post-treatment plasma glucose concentrations were not significantly different in the two groups, but serum insulin concentrations were significantly higher following Pred therapy (P<0.05). Serum fructosamine concentrations were not significantly different pre- and post-treatment with Pred, although previous studies had shown that CsA treatment increased fructosamine concentrations (P<0.005). The two treatment groups were recruited in a similar timeframe, were numerically matched and there were no differences in CADESI-03 and EPS scores between the CsA and Pred groups either before or after treatment. Thus, both CsA and Pred treatment were associated with mild disturbances in glucose metabolism, but only CsA therapy resulted in a significant increase in fructosamine concentrations. This information may be relevant to clinicians when considering therapeutic options for dogs with atopic dermatitis which already have impaired glucose homeostasis.     

Ureterocolonic anastomosis in clinically normal dogs

Ureterocolonic anastomosis was evaluated in 13 clinically normal dogs. Urinary continence was maintained after surgery, and the procedure was completed without technique errors in all but 2 dogs. Three dogs died within 5 weeks (2 of undetermined causes and 1 of aspiration pneumonia and neurologic disease), and 1 dog was euthanatized 4 months after surgery because of neurologic signs. Two healthy dogs were euthanatized 3 months after surgery for light microscopic evaluation of their kidneys. Five dogs were euthanatized 6 months after surgery for light microscopic evaluation of their kidneys. Gastrointestinal and neurologic disturbances developed in 4 dogs at various postoperative intervals. Plasma ammonia concentration measured in 2 dogs with neurologic signs was increased. Plasma ammonia concentration measured in 5 dogs without neurologic signs was within normal limits. All 5 dogs, in which metabolic acidosis was diagnosed, had high normal or above normal serum chloride concentration. Serum urea nitrogen values were increased after surgery because of colonic absorption of urea. Serum creatinine concentration was increased in 1 dog 6 months after surgery. Individual kidney glomerular filtration rate was reduced in 38% (3/8) of the kidneys from 4 other dogs at 6 months after surgery. Of 5 dogs euthanatized at 3 to 4 months after surgery, 4 had bilateral pyelitis, and 1 had unilateral pyelonephritis. Six months after surgery, pyelonephritis was diagnosed in 40% (4/10) of the kidneys from 5 dogs. The ureterocolonic anastomosis procedure is a salvage procedure that should allow complete cystectomy. However, variable degrees of metabolic acidosis, hyperammonemia, and neurologic disease may result.     

Association of pruritus with anxiety or aggression in dogs

OBJECTIVE: To evaluate the association between pruritus and anxiety-related and aggressive behaviors in dogs. DESIGN: Cross-sectional survey. ANIMALS: 238 dogs between 1 and 8 years old. PROCEDURES: Information including a score for general degree of pruritus (visual analogue scale from 0 to 10) and frequency of anxiety-related and aggressive behaviors was collected via a survey distributed to clients at 3 privately owned practices. RESULTS: Median score for pruritus was 2.4. Dogs were assigned to 2 groups on the basis of pruritus score (nonpruritic [0 to 2.4] and pruritic [2.5 to 10]). There was no significant difference between pruritic and nonpruritic dogs with regard to aggression or with regard to reactivity to being alone; to thunderstorms or noises; or to unfamiliar people, animals, or objects. Post hoc analysis revealed significantly more reactivity to thunderstorms or noises in dogs treated with glucocorticoids (18/37 [49%]) than in those not administered glucocorticoids (57/197 [29%]). CONCLUSIONS AND CLINICAL RELEVANCE: An association was not detected between pruritus and aggressive, anxious, or fearful behavior in dogs. There was greater reactivity to thunderstorms or noises in glucocorticoid-treated dogs. These findings do not preclude the possibility of a relationship between certain dermatoses or pruritic conditions and behavior. However, a concurrent behavioral abnormality cannot be assumed to result from a dermatosis and be expected to resolve with treatment of only the skin disease. Dogs with behavioral disorders and pruritic disease require primary treatment of both conditions. Additional studies to examine the effect of disease and glucocorticoids on canine behavior are warranted.     

Use of narcotic antagonists to modify stereotypic self-licking, self-chewing, and scratching behavior in dogs

We evaluated 2 narcotic antagonists, naltrexone and nalmefene, for treatment of refractory self-licking, self-chewing, and scratching behavior in dogs. Eleven dogs with various irritative or pruritic disorders were medicated with naltrexone (1 mg/kg of body weight, sc) or nalmefene (1 to 4 mg/kg, sc), after a period of control observation during which the dogs had not been medicated. The time for which the dogs were involved in self-licking, self-chewing, or scratching was determined retrospectively by analysis of videotapes. The rates of involvement in either activity before and after treatment were calculated and compared statistically. Treatment with a narcotic antagonist significantly reduced the time spent self-licking, self-chewing, or scratching in 7 of 11 dogs, was partially effective in 3 dogs, and was ineffective in one dog. Dogs with acral lick dermatitis responded most to treatment.