首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
This study compared the pharmacokinetic and pharmacodynamic profiles of an extemporaneously prepared (compounded) atenolol paste and suspension for oral administration, against the commercially available divided tablet in healthy cats. Eleven healthy cats (mean: age 4 ± 0.4 year, weight 5.0 ± 0.7 kg) were dosed twice-daily with 12.5 mg atenolol (tablet, paste or suspension) for 7 days in a randomized cross-over design with a 7-day wash-out period. On day 7, an electrocardiogram was performed before and immediately after stress provocation (jugular venipuncture) at prestudy screening, and at 2, 6 and 12 h after morning dosing. Systolic arterial blood pressure (BP) was assessed following the second electrocardiogram. Plasma was collected at prestudy screening, and at 1, 2, 6 and 12 h to measure atenolol plasma concentrations. Mean atenolol dose was 2.5 mg/kg (range: 2.1-3.3 mg/kg). Stress-induced rise in heart rate was attenuated (P < 0.05) at every time point compared to baseline for all formulations. Although the paste significantly attenuated stress-induced elevation in heart rate at all time points, the effect was not consistently equivalent to the tablet. The BP was not altered (P > 0.05) at any time point by any formulation. In conclusion, there were no significant differences (P > 0.05) in any of the pharmacokinetic parameters or pharmacodynamic profiles of the paste and suspension compared to the commercially available tablet.  相似文献   

2.
A three-way crossover study was carried out in 10 dogs and nine cats to establish the pharmacokinetic parameters of the semi-synthetic cephalosporin antibiotic, cephalexin sodium, when administered orally, subcutaneously or intramuscularly. Ten dogs received a subcutaneous or intramuscular injection of 10 mg/kg bodyweight cephalexin or an oral dose of three 50 mg cephalexin tablets; the peak serum concentrations achieved were 24.9, 31.9 and 18.6 micrograms/ml, respectively, and the times taken to reach these peak levels were 1.2, 0.9 and 1.8 hours. Nine cats received either a subcutaneous or intramuscular dose of 0.25 ml cephalexin suspension (approximately 20 mg/kg bodyweight) or an oral dose of one 50 mg tablet; the peak serum concentrations achieved were 54.0, 61.8 and 18.7 micrograms/ml for the subcutaneous, intramuscular and oral administrations respectively, with times to peak concentrations of 1.1, 0.7 and 2.6 hours.  相似文献   

3.
To evaluate the effects of compensated heart failure (HF) on digoxin pharmacokinetic properties in cats, 6 cats with dilated cardiomyopathy were compared with 6 clinically normal (control) cats. Digoxin tablets were administered at a dosage of 0.01 mg/kg of body weight, q 48 h for approximately 10 days, until presumed steady state was reached. Both groups were treated concomitantly with aspirin, furosemide, and a commercial low-salt diet. Retrospectively, control and HF cats were calculated to be at 95% and 97% steady state, respectively. At the time blood samples were collected, HF cats were clinically compensated. Serum digoxin concentration [( DXN]) was determined by radioimmunoassay on samples drawn immediately before and 1, 2, 4, 8, 12, 24, 34, and 48 hours after digoxin administration. Measured and calculated values (peak, 8-hour, and mean [DXN]; elimination half-life [t1/2]; oral clearance; and hours during which [DXN] was in the toxic range) were not significantly different between control and HF cats. To predict individual propensity for digoxin intoxication, serum creatinine and urea concentrations and sulfobromophthalein dye retention were measured in control and HF cats prior to the onset of treatment with digoxin. There was no statistically significant correlation between serum creatinine and urea concentrations when compared with sulfobromophthalein dye retention nor between any of these values and digoxin peak, 8-hour, and mean concentrations or t1/2, oral clearance, or hours during which [DXN] was in the toxic range. Mean serum creatinine and urea nitrogen concentrations were significantly greater (P less than 0.01) and sulfobromophthalein dye retention approached significant prolongation (P less than 0.06) in HF cats, compared with that in control cats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
Steady-state serum digoxin concentration ([digoxin]) was measured for 48 hours in 6 healthy cats after they were treated with digoxin tablets (0.01 mg/kg of body weight, q 48 h) for 10 days and again after concurrent treatment of identical duration with orally administered digoxin, aspirin (80 mg, q 48 h), furosemide (2 mg/kg, q 12 h), and a commercial low-salt diet. The concurrent treatment substantially altered digoxin pharmacokinetic properties, with a resultant increase in peak (mean +/- SEM; from 2.1 +/- 0.35 to 3.3 +/- 0.6 ng/ml), 8-hour (from 1.4 +/- 0.35 to 2.5 +/- 0.64 ng/ml), and 48-hour mean (from 1.1 +/- 0.22 to 2.2 +/- 0.57 ng/ml) serum [digoxin]; an increase in the number of hours during which serum [digoxin] was in the toxic range (from 3 +/- 1.7 to 24.7 +/- 9.8 h); and a decrease in oral clearance (from 0.15 +/- 0.04 to 0.08 +/- 0.02 L/h.kg). Of these differences, all but the 8-hour serum [digoxin] were significant at P less than 0.05. Similar sampling procedures were performed in 3 cats after administration of digoxin alone (0.01 mg/kg, q 48 h) until steady-state conditions were reached (10 days) and again after an additional 10 days of treatment. Differences were not noticed in digoxin pharmacokinetic properties. Eight-hour serum [digoxin] was shown to correlate closely with the mean serum [digoxin] at steady-state conditions when digoxin was administered every 48 hours. Variation in digoxin pharmacokinetic properties was noticed between cats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
OBJECTIVE: To evaluate effects of dietary insoluble fiber on control of glycemia in cats with naturally acquired diabetes mellitus. DESIGN: Randomized controlled crossover trial. ANIMALS: 16 cats with naturally acquired diabetes mellitus. PROCEDURE: Cats were fed a diet high in insoluble fiber (HF) containing 12% cellulose (dry-matter basis) or a diet low in insoluble fiber (LF) for 24 weeks; they were fed the other diet for the subsequent 24 weeks. Caloric intake and insulin treatment were adjusted to maintain stable body weight and control of glycemia, respectively. Cats were allowed an adaptation period of 6 weeks after initiation of a diet, after which control of glycemia was evaluated at 6-week intervals for 18 weeks. Variables assessed included serum glucose concentration measured during the preprandial state, blood glycated hemoglobin concentration, serum glucose concentration measured at 2-hour intervals for 12 hours beginning at the time of the morning insulin injection, 12-hour mean serum glucose concentration, and mean fluctuation in serum glucose concentration from the 12-hour mean serum glucose concentration. RESULTS: Mean daily caloric intake, body weight, or daily insulin dosage did not differ significantly between cats when fed HF and LF diets. Mean preprandial serum glucose concentration, most post-prandial serum glucose concentrations, and the 12-hour mean serum glucose concentration were significantly lower when cats consumed the HF diet, compared with values when cats consumed the LF diet. CONCLUSIONS AND CLINICAL RELEVANCE: These results support feeding a commercially available diet containing approximately 12% insoluble fiber (dry-matter basis) to cats with naturally acquired diabetes mellitus.  相似文献   

6.
OBJECTIVE: To describe the disposition of and pharmacodynamic response to atenolol when administered as a novel transdermal gel formulation to healthy cats. ANIMALS: 7 healthy neutered male client-owned cats. PROCEDURES: Atenolol was administered either orally as a quarter of a 25-mg tablet or as an equal dose by transdermal gel. Following 1 week of treatment, an ECG and blood pressure measurements were performed and blood samples were collected for determination of plasma atenolol concentration at 2 and 12 hours after administration. RESULTS: 2 hours after oral administration, 6 of 7 cats reached therapeutic plasma atenolol concentrations with a mean peak concentration of 579 +/- 212 ng/mL. Two hours following transdermal administration, only 2 of 7 cats reached therapeutic plasma atenolol concentrations with a mean peak concentration of 177 +/- 123 ng/mL. The difference in concentration between treatments was significant. Trough plasma atenolol concentrations of 258 +/- 142 ng/mL and 62.4 +/- 17 ng/mL were achieved 12 hours after oral and transdermal administration, respectively. A negative correlation was found between heart rate and plasma atenolol concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Oral administration of atenolol at a median dose of 1.1 mg/kg every 12 hours (range, 0.8 to 1.5 mg/kg) in cats induced effective plasma concentrations at 2 hours after treatment in most cats. Transdermal administration provided lower and inconsistent plasma atenolol concentrations. Further studies are needed to find an effective formulation and dosing scheme for transdermal administration of atenolol.  相似文献   

7.
This study was designed to evaluate the cats' acceptance and compliance of the owners and cats towards an extemporaneously prepared palatable compounded atenolol (paste and suspension) formulation in comparison to the commercially obtained tablet, in a randomised, cross-over study design.The three formulations were prescribed twice daily for 6 days to 13 healthy privately-owned cats of 13 different owners, with varying levels of experience in medicating cats. Daily compliance was evaluated via an owner-completed diary, completed after each dose administered. Owner's experience and preference of the formulation was evaluated via questionnaires given prior to, at the end of each treatment protocol, and upon completion of the study. Although compounded suspension was association with fewest missed doses, the majority of cat owners expressed a preference for the divided tablet. Atenolol tablets, compounded paste and suspension acceptance and compliance were comparable. Further work is now required to assess the amount and stability of the active ingredient and the robustness of the paste and suspension formulations prior to any bioavailability comparisons between the formulations.  相似文献   

8.
The pharmacokinetic profile and bioavailability of a long-acting formulation of cephalexin after intramuscular administration to cats was investigated. Single intravenous (cephalexin lysine salt) and intramuscular (20% cephalexin monohydrate suspension) were administered to five cats at a dose rate of 10 mg/kg. Serum disposition curves were analyzed by noncompartmental approaches. After intravenous administration, volume of distribution (Vz), total body clearance (Clt), elimination constant (λz), elimination half-life (t½λ) and mean residence time (MRT) were: 0.33 ± 0.03 L/kg; 0.14 ± 0.02 L/h kg, 0.42 ± 0.05 h−1, 1.68 ± 0.20 h and 2.11 ± 0.25 h, respectively. Peak serum concentration (Cmax), time to peak serum concentration (Tmax) and bioavailability after intramuscular administration were 15.67 ± 1.95 μg/mL, 2.00 ± 0.61 h and 83.33 ± 8.74%, respectively.  相似文献   

9.
Serum concentrations of gentamicin in cats   总被引：1，自引：0，他引：1  
Twenty-one adult cats, allotted into 2 groups, were given gentamicin sulfate at dosages of either 5.0 mg/kg of body weight or 2.5 mg/kg as a single IM injection. During a 24-hour period, serum concentrations of gentamicin were measured serially, using a fluorescence immunoassay. The mean peak serum concentration of gentamicin in cats given 5.0 mg/kg was 23.1 micrograms/ml at postinjection hour (PIH) 0.5; thereafter, the mean serum concentration steadily decreased to 2.0 micrograms/ml at PIH 24. The mean peak serum concentration for cats administered 2.5 mg/kg was 9.1 micrograms/ml at PIH 0.5; thereafter, the mean serum concentration steadily decreased to 1.3 micrograms/ml at PIH 12. Serum therapeutic concentrations, without exceeding toxic concentrations, were attained at the 2.5 mg/kg dosage.  相似文献   

10.
The non-steroidal anti-inflammatory drug (NSAID) carprofen was administered to dogs as a mixed-micelle solution at a dose rate of 0–7 mg/kg intravenously, as a palatable paste at a dose rate of 0–7 mg/kg orally, and as an oral tablet formulation at a dose rate of 0–7 mg/kg and 4-0 mg/kg orally for pharmacokinetic studies. It was also administered as an oral tablet formulation at a dose rate of 9-0 mg/kg orally daily for 14 days in a tolerance study. The pharmacokinetics following intravenous administration at a dose rate of 0–7 mg/kg indicate that carprofen has a small volume of distribution (Vd area = 0–09-0-25 litres), a slow systemic clearance (Cls = 1–34-5-57 ml/min) and an elimination half-life of 3–20-11-77 hours. Both oral paste and tablet preparations were highly bioavailable and absorption was proportional to dose rate at 0–7 mg/kg and 4-0 mg/kg bodyweight. Given once daily at dose rates likely to be used clinically it is unlikely to accumulate in the plasma. Carprofen administered as a palatable paste at a dose rate of 0–7 mg/kg did not inhibit serum thromboxane generation and this drug may therefore have a mode of action different from most NSAIDs. Carprofen was well tolerated when administered as an oral tablet formulation at a dose rate of 9.0 mg/kg daily for 14 days in healthy beagle dogs.  相似文献   

11.
Hydrochlorothiazide (1 mg/kg PO q12h) or placebo was administered to healthy cats for 2 weeks in a masked, placebo-controlled, crossover-design study, and 24-hour urine samples were collected. When cats received hydrochlorothiazide, 24-hour urine volume, ammonia, chloride, creatinine, magnesium, oxalic acid, phosphate, potassium, and sodium were significantly higher than when cats received placebo. Hydrochlorothiazide was associated with significantly lower urinary saturation for calcium oxalate, but no difference was found in 24-hour urine calcium and citrate, urinary saturation for struvite, or blood ionized calcium. Hydrochlorothiazide decreased urinary saturation for calcium oxalate and could be useful in managing cats with calcium oxalate uroliths. Results of this study, however, should not be extrapolated to cats that form calcium oxalate uroliths.  相似文献   

12.
Carbimazole, a prodrug of methimazole, is used in the treatment of hyperthyroidism in cats. The pharmacokinetics of methimazole was investigated in healthy cats following oral administration of 15 mg of carbimazole as a controlled-release tablet (Vidalta®, Intervet). The controlled-release tablet did not produce a pronounced concentration peak and methimazole was present in the circulation for a sustained period, compared with a conventional tablet formulation. The time to reach peak concentrations after carbimazole administration was quite long (tmax 6 h). The absolute bioavailability of carbimazole was around 88 ± 11%. Repeated oral administration daily for 13 consecutive days did not lead to accumulation of methimazole in plasma. The extent of absorption of carbimazole was about 40% higher when administered to cats that had been fed compared to fasted cats. The relative oral bioavailability of methimazole following administration of the controlled-release tablets was similar to that of a conventional release formulation (83 ± 21%). The pharmacokinetics of this controlled-release formulation of carbimazole supports its use as a once daily treatment (both as a starting dose and for maintenance therapy) for cats with hyperthyroidism.  相似文献   

13.
Background: Methimazole suppresses thyroid hormone synthesis and is commonly used to treat feline hyperthyroidism. The degree of variation in thyroid hormone concentrations 24 hours after administration of methimazole and optimal time for blood sampling to monitor therapeutic efficacy have not been determined.
Objective: To assess thyroid hormone concentration variation in serum of normal and hyperthyroid cats after administration of methimazole.
Animals: Four healthy cats and 889 retrospectively acquired feline thyroid hormone profiles.
Methods: Crossover and retrospective studies . In the crossover study, healthy cats were treated with increasing doses of oral methimazole until steady state of thyroid suppression was achieved. Thyroid hormones and thyroid stimulating hormone (TSH) were serially and randomly monitored after methimazole. Paired t -tests and a 3-factor analysis of variance were used to determine differences between thyroid hormone concentrations in treated and untreated cats in the crossover study. Thyroid profiles from methimazole-treated hyperthyroid cats were retrieved from the Diagnostic Center for Population and Animal Health database and reviewed. Linear regression analysis evaluated relationships of dosage (mg/kg), dosing interval (q24h versus q12h), and time after methimazole to all thyroid hormone concentrations.
Results: All serum concentrations of thyroid hormones were significantly suppressed and TSH was significantly increased for 24 hours after administration of oral methimazole in healthy cats ( P < .005). In hyperthyroid cats, there were no significant relationships between thyroid hormone concentrations and time postpill or dosing interval.
Conclusions: Timing of blood sampling after oral methimazole administration does not appear to be a significant factor when assessing response to methimazole treatment.  相似文献   

14.
The pharmacokinetic behaviour of ivermectin was investigated in adult llamas (Lama glama) by using high performance liquid chromatography with a lower limit of quantification of 2 ng/ml to measure its concentration in serum. Llamas were treated with one of three commercial formulations (injectable, pour-on or oral paste) at dosages recommended by the manufacturer, or with an experimental injectable sustained-release formulation. In five llamas given 1 per cent ivermectin subcutaneously at 200 microg/kg, the median peak serum concentration (Cmax) was 3 ng/ml and the area under the serum concentration-time curve (AUC) was 13.5 ng x day/ml. In six llamas treated topically with 0.5 per cent ivermedin pour-on at 500 microg/kg, Cmax was 2.5 ng/ml or less and the AUC was 7.75 ng x day/ml or less. In seven llamas with measurable concentrations of ivermedin, the median times to peak serum concentration (tmax) were six days after subcutaneous injection and seven days after treatment with the pour-on formulation. In six llamas, the serum concentration of ivermectin remained less than 2 ng/ml for 124 hours after treatment with a 1.87 per cent oral paste at 200 microg/kg. In five llamas treated subcutaneously with 25 per cent ivermectin sustained-release microspheres at 1500 microg/kg, the median Cmax was 5 ng/ml and the median AUC was 224 ng x day/ml.  相似文献   

15.
The goals of this study were to compare the efficacy of once-daily administered Glargine insulin to twice-daily administered Lente insulin in cats with diabetes mellitus and to describe the use of a high-protein, low-carbohydrate diet designed for the management of diabetes mellitus in cats. All cats with naturally occurring diabetes mellitus were eligible for inclusion. Baseline testing included a physical examination, serum biochemistry, urinalysis and urine culture, serum thyroxine concentration, and serum fructosamine concentration. All cats were fed the high-protein, low-carbohydrate diet exclusively. Cats were randomized to receive either 0.5 U/kg Lente insulin q12h or 0.5 U/kg Glargine insulin q24h. Re-evaluations were performed on all cats at weeks 1, 2, 4, 8, and 12, and included an assessment of clinical signs, physical examination, 16-hour blood glucose curve, and serum fructosamine concentrations. Thirteen cats completed the study (Lente, n = 7, Glargine, n = 6). There was significant improvement in serum fructosamine and glucose concentrations in all cats but there was no significant difference between the 2 insulin groups. Four of the 13 cats were in complete remission by the end of the study period (Lente, n = 3; Glargine, n = 1). The results of the study support the use of once-daily insulin Glargine or twice-daily Lente insulin in combination with a high-protein, low-carbohydrate diet for treatment of feline diabetes mellitus.  相似文献   

16.
Objective: To compare the effect of a balanced isotonic crystalloid solution with that of 0.9% sodium chloride on the acid–base and electrolyte status of cats with urethral obstruction.
Design: Randomized prospective clinical trial.
Setting: Academic veterinary emergency room.
Animals: Sixty-eight cats with naturally occurring urethral obstruction.
Interventions: Cats were randomized to receive either a balanced isotonic crystalloid solution (Normosol-R, n =39) or 0.9% sodium chloride ( n =29) for fluid therapy. Baseline venous blood gas and blood electrolyte values were obtained at the time of admission and at intervals during the course of therapy.
Measurements and main results: Baseline values were similar between groups. Cats receiving Normosol-R had a significantly higher blood pH at 12 hours, a significantly greater increase in blood pH from baseline at 6 and 12 hours, as well as a significantly higher blood bicarbonate concentration at 12 hours and a significantly greater increase in blood bicarbonate from baseline at 6 and 12 hours. Conversely, the increase in blood chloride from baseline was significantly higher at 2, 6, and 12 hours in cats receiving 0.9% sodium chloride. There were no significant differences in the rate of decline of blood potassium from baseline between groups. Subgroup analysis of hyperkalemic cats (K+>6.0 mmol/L) and acidemic cats (pH<7.3) yielded similar findings.
Conclusions: While both crystalloid solutions appear safe and effective for fluid therapy in cats with urethral obstruction, the use of a balanced electrolyte solution may allow more rapid correction of blood acid–base status within the first 12 hours of fluid therapy. The use of a potassium-containing balanced electrolyte solution does not appear to affect the rate of normalization of blood potassium in treated cats with urethral obstruction.  相似文献   

17.
Five adult cats were given 100 mg chloramphenicol per os on five occasions: twice in tablet form, twice in capsules which also contained barium sulphate, and once in capsules without barium. Plasma samples for chloramphenicol assay were obtained on either a 'standard' schedule (four samples collected within 8 h of dosing with tablet, plain capsule or capsule including barium) or a 'frequent' schedule (nine samples collected within 8 h of dosing with tablet or capsule including barium). With frequent sampling, abdominal radiographs were taken at intervals after administration of capsules. No differences were found with the frequent schedule between tablet and capsule with regard to antibiotic concentrations at each sampling, peak concentrations, or area under the curve of plasma concentration versus time. Standard sampling gave similar drug concentrations to those obtained with frequent sampling. Delayed absorption (defined as plasma chloramphenicol concentration < 5 μg/ml for 1.5 h after dosing) occurred after six of the twenty-five administrations: it was not related to the frequency of sample collection or the use of capsules rather than tablets, but occurred mainly in certain cats. Poor absorption was shown radiographically in one cat to be associated with delayed dispersal of capsular contents in the gut.  相似文献   

18.
Serial determination of thyroxine concentrations in hyperthyroid cats   总被引：2，自引：0，他引：2  
Serum thyroxine (T4) concentrations of 10 hyperthyroid cats were measured at hourly intervals between 9 AM and 4 PM. In 5 cats, blood samples were obtained by jugular venipuncture; the remaining 5 cats had blood samples obtained from jugular catheters. Over the 7-hour period, a significant temporal (diurnal) variation was not identified in the serum T4 concentrations of the cats (P greater than 0.01). The lowest mean serum T4 concentration (9.1 micrograms/dl) was measured at 3 PM and was 14.2% less than the highest mean serum T4 concentration (10.6 micrograms/dl) measured at 9 AM. Though there were fluctuations in serum T4 concentrations during the 7-hour period, the differences were not systematic. The maximal variation in serum T4 concentrations over the 7-hour period averaged less than 21%. Despite the random variations during the 7-hour period, none of the measured serum T4 concentrations was in the normal range. Measurement of serum T4 concentration from randomly obtained blood samples was determined to be reliable for diagnosing feline hyperthyroidism.  相似文献   

19.
The plasma and serum concentrations of phenylbutazone (PBZ) and oxyphenbutazone were measured in 158 Thoroughbred horses after various doses of PBZ wer given. All horses were competing or training at racetracks in various parts of the country. All horses used in the study had not been given PBZ 24 hours before they were placed on a specific dosage schedule. Samples were collected 24 hours after the last PBZ administration. Four grams of PBZ were given daily by stomach tube, paste, or tablet for 3 days. On day 4, 24 hours before sample collection, an IV dose of 2 g of PBZ was given, regardless of the dose and method of administration. The 24-hour PBZ plasma concentrations were 3.51, 6.13, and 6.40 micrograms/ml, respectively. After 2 g of PBZ was administered IV daily for 4 days, the plasma PBZ concentration was 4.16 g/ml; after a single 2-g IV administration, the serum concentration was 0.87 g/ml. Concentrations of oxyphenbutazone were 3.35 (stomach tube), 4.29 (paste), 3.60 (tablet), 3.65 (4-day IV), and 1.11 g/ml (single IV). A significant relationship was not found between the serum and the urinary concentrations at this 24-hour measurement. Split samples sent to various laboratories confirmed the stability of high-performance liquid chromatography as a method of analysis.  相似文献   

20.
The pharmacokinetics of sodium and lysine cephalexins were investigated after intravenous and intramuscular administration of a single dose rate of 30 mg.kg-1 body weight in calves. The data for the two salts administered intravenously were pooled, the resulting pharmacokinetic disposition of cephalexin indicating a distribution half-time (t1/2 alpha) and an elimination half-time (t1/2 beta) of 9.78 and 62.0 min, respectively. Following intramuscular administration some pharmacokinetic differences were recorded between the cephalexin preparations: lysine cephalexin was more rapidly eliminated (t1/2kel = 55.2 min) than sodium cephalexin (t1/2kel = 89.8 min), although the peak blood level was higher and attained after a longer time with lysine cephalexin.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号