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Summary:

The efficacy of microcrystalline desoxycorticosterone pivalate (docp) therapy was evaluated in 60 dogs with hypoadrenocorticism. Fifty-one of the dogs were being treated with either docp or fludrocortisone acetate prior to entering the study. The disease had been recently diagnosed in 9 dogs that were not under maintenance treatment prior to entering the study. Desoxycorticosterone pivalate (2.2 mg/kg of body weight, im) was administered on days 0, 25, and 50. Physical examination was performed, and blood samples were obtained for serum biochemical analysis (Na+, K+, and bun concentrations) on days 0, 14, 25, 39, 50, 64, and 75. On day 75 of the study, a final physical examination was performed and the course of treatment was evaluated.

Sixty-eight percent (41/60) of the dogs had normal physical findings on day 0 vs 87% (52/60) on day 75. Mean (±sd) body weight increased from 24.8 ± 12.7 kg on day 0 to 26.2 ± 13.7 kg on day 75. Mean serum Na+ (137.7 ± 8.5 mEq/L) and K+ (5.6 1.0 mEq/L) concentrations and Na+-to-K+ ratio (25.4 ± 5.0:1) were outside normal reference limits on day 0. By day 75, serum Na+ (144.3 ± 4.8 mEq/L) and K+ (4.9 ± 0.8 mEq/L) concentrations and Na+-to-K+ ratio (30.4 ± 5.1:1) were normal and were significantly (P < 0.01) improved, compared with the corresponding values on day 0.

Of the 60 dogs, 58 (97%) regained the loss in body weight, appetite, and muscular strength while given docp; once achieved, these improvements were maintained. These 58 dogs did not vomit or have diarrhea, common problems in dogs with hypoadrenocorticism. The mineralocorticoid (docp) alone was not adequate to correct all clinical signs associated with endogenous mineralocorticoid and glucocorticoid deficiencies, which are typical of hypoadrenocorticism in dogs. Thus, 22 of the 58 dogs had glucocorticoid-responsive clinical signs of disease (lethargy, n = 10; anorexia, n = 8; weakness and hypoadrenal crisis, n = 2 each). These signs resolved in response to initiation of glucocorticoid therapy (prednisolone, 2.5 mg/d, po) and/or adjustments in docp dose or dosing interval. Ten dogs developed polyuria, polydipsia, or both during the study; these signs improved when the dose of prednisolone (n = 9) or docp (n = 1) was reduced. All owners but 1 chose to continue docp therapy after the trial ended, and all dogs remained free of clinical signs associated with hypoadrenocorticism for at least 1 year after the study ended.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether 1% diclofenac liposomal suspension (DLS) ointment would be absorbed transdermally and attenuate experimentally induced subcutaneous inflammation in horses.

Animals—7 healthy adult horses

Procedure—Inflammation was produced by injecting 1% sterile carrageenan into subcutaneously implanted tissue cages 8 hours before (time –8) and at the time of application of test ointment. A crossover design was used. Horses received 1 of 2 treatments (topically administered control or DLS ointments) during 48 hours of carrageenan-induced subcutaneous inflammation. A single application of test ointment (7.2 g) was applied over each tissue cage (time 0). Samples of transudate and blood were collected at –8, 0, 6, 12, 18, 24, 30, 36, and 48 hours. Plasma and transudate diclofenac concentrations were determined by use of high-performance liquid chromatography. Transudate concentrations of prostaglandin E2 (PGE2) were determined with a competitive enzyme immunoassay.

Results—DLS was absorbed transdermally. The highest concentration (mean ± SEM, 76.2 ± 29 ng/mL) was detectable in tissue-cage fluid within 18 hours after application. Minimal concentrations of diclofenac were detectable in plasma. Application of DLS significantly decreased transudate concentrations of PGE2 at 6 and 30 hours. Decreases in PGE2 concentration were observed in the DLS group at all collection times.

Conclusions and Clinical Relevance—A single topical application of DLS resulted in concentrations of diclofenac in transudate within 6 hours and significantly attenuated carrageenan-induced local production of PGE2. Results of this study suggest that DLS is readily absorbed transdermally and may be efficacious for reducing subcutaneous inflammation in horses. ( Am J Vet Res 2004;65:271–276)

Full access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate effects of protamine zinc insulin (PZI) on control of glycemia in cats with newly diagnosed diabetes mellitus or poorly controlled diabetes.

Design—Clinical trial.

Animals—67 diabetic cats.

Procedure—34 cats with newly diagnosed diabetes and 33 cats with poorly controlled diabetes were treated with PZI twice daily for 45 days. Control of glycemia was assessed on days 7, 14, 30, and 45 by evaluation of clinical response, change in body weight, serum fructosamine concentration, blood glucose concentration measured 1, 3, 5, 7, and 9 hours after administration of PZI, lowest blood glucose concentration, and mean blood glucose concentration during the 9-hour period after administration. Adjustments in dosage of PZI were made as needed to attain control of glycemia.

Results—For all cats, a significant increase in mean dosage of PZI and significant decreases in 9-hour mean blood glucose concentration, lowest mean blood glucose concentration, and mean serum fructosamine concentration were detected. For cats with poorly controlled diabetes, 9-hour mean blood glucose concentration and mean serum fructosamine concentration were significantly decreased on day 45, compared with day 0. Ninety percent of owners reported improvement or resolution of clinical signs by day 45.

Conclusions and Clinical Relevance—Results suggest that PZI was effective for control of glycemia in cats with newly diagnosed or poorly controlled diabetes and may be used as an initial treatment or as an alternative treatment in cats that do not respond to treatment with other types of insulin. ( J Am Vet Med Assoc 2001;218:38–42)

Full access
in Journal of the American Veterinary Medical Association

Summary

Desoxycorticosterone pivalate was administered im to juvenile Beagles at 0, 2.2, 6.6, or 11 mg/kg of body weight daily over a consecutive 3-day period every 28 days (equivalent to a cumulative monthly dosage of 0, 6.6, 19.8, or 33 mg/kg) for 6 months. Polyuria, polydipsia, and decreases in serum potassium and bun concentrations were detected while the dogs were being treated. Transient increases in serum sodium concentrations also were detected. The treated males had significant decreases in body weight gain, resulting in an 18% decrease in body weight in the 11-mg/kg dosage group, compared with the controls. The weights of the adrenal glands, epididymides, and testes also were lower in the treated males. Organ weights for the 2.2, 6.6, and 11-mg/kg dosage groups were: 86, 79, and 69%, respectively, of the controls (adrenal glands); 80, 70, and 68%, respectively, of the controls (epididymides); and, 79, 75, and 67%, respectively, of the controls (testes). When normalized to body weight, these decreases in organ weight were still dosage-dependent, but the differences were less remarkable. In contrast, the relative weight (to body weight) of the kidneys (males and females) and of the thyroid and parathyroid glands (males) were higher dosage-dependently. All of the treatment-related effects, other than organ and body weight changes, appeared to be reversible following the cessation of treatment. On the basis of these results, it was concluded that treatment with desoxycorticosterone pivalate could be tolerated, even when given at dosages 15-fold the therapeutic dosage of 2.2 mg/kg every 25 days.

Free access
in American Journal of Veterinary Research

Summary

Twenty-four specific-pathogen-free Beagles were each given 50 cysticerci of Taenia pisiformis that had been harvested from experimentally infected rabbits. Quantitative fecal egg counts and fecal screening for recovery of passed segments were performed on postinoculation days 56 through 70. Twenty-three of 24 dogs fed cysticerci developed patent infections. The 23 dogs with patent infections were assigned to 1 of 2 groups and treated with nitroscanate or a placebo 60 days after inoculation. Egg counts in the treated dogs had markedly decreased by the second day after treatment, and by the sixth day after treatment, segments were not found in the feces of any of the treated animals. The control dogs continued to pass eggs and segments in their feces throughout the 9 days after treatment. The dogs were euthanatized and necropsied 70 days after being inoculated. At necropsy, the mean number of scolices recovered from control dogs was 24.6, the mean number of scolices recovered from treated dogs was 0.25. Worms recovered from the control dogs were intact, gravid cestodes. Efficacy of treatment with nitroscanate at a mean dosage of 56 mg/kg of body weight was 98.9%.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate and compare characteristics of a commercially manufactured protamine zinc insulin (PZI) product and PZI products obtained from various compounding pharmacies.

Design—Evaluation study.

Sample—112 vials of PZI (16 vials of the commercially manufactured product and 8 vials from each of 12 compounding pharmacies) purchased over an 8-month period.

Procedures—Validated methods were used to analyze 2 vials of each product at 4 time points. Appearance, endotoxin concentration, crystal size, insulin concentration in the supernatant, pH, total insulin and zinc concentrations, and species of insulin origin were evaluated.

Results—All 16 vials of commercially manufactured PZI met United States Pharmacopeia (USP) specifications. Of 96 vials of compounded PZI, 1 (1 %) contained a concentration of endotoxin > 32 endotoxin U/mL, 23 (24%) had concentrations of insulin in the supernatant > 1.0 U/mL, and 45 (47%) had pH values < 7.1 or > 7.4; all of these values were outside of specifications. Several vials of compounded PZI (52/96 [54%]) did not meet specifications for zinc concentration (0.06 to 0.1 mg/mL for 40 U of insulin/mL, 0.075 to 0.12 mg/mL for 50 U of insulin/mL, and 0.15 to 0.25 mg/mL for 100 U of insulin/mL), and total insulin concentration in 36 [38%] vials was < 90% of the labeled concentration.

Conclusions and Clinical Relevance—Only 1 of 12 compounded PZI products met all USP specifications in all vials tested. Use of compounded PZI insulin products could potentially lead to serious problems with glycemic control in veterinary patients.

Full access
in Journal of the American Veterinary Medical Association