Azithromycin monograph pdf

The retention time of the azithromycin peak of the Sample solution corresponds to that of the Standard solution, as obtained in the Assay. Adjust with about 6 mL of 10 N potassium hydroxide to a pH of Diluent: Dissolve 2. Adjust with 10 N potassium hydroxide to a pH of 8. Standard stock solution: 0. Swirl, and sonicate as necessary. Standard solution: 3. Swirl, and sonicate to dissolve. Dilute with Mobile phase to volume.

System suitability solution: 3. Transfer the contents of a container of Azithromycin for Oral Suspension to a suitable volumetric flask.

Dilute with Diluent to volume. Transfer 40 mL of this suspension to a stoppered centrifuge tube, and centrifuge for 20 min. Use the supernatant to prepare Sample solution 1. Sample stock solution 2 where packaged in a multiple-unit container : 0. Page 2 sur 4 Azithromycin for Oral Suspension as directed in the labeling. Transfer a suitable aliquot of the suspension so obtained, freshly mixed and free from air bubbles to a suitable volumetric flask to obtain to obtain a final concentration of 0.

Transfer 40 mL of the suspension so obtained to a stoppered centrifuge tube, and centrifuge for 20 min. Use the supernatant to prepare Sample solution 2. Sample solution 1: 3. Related Papers.

By Md. Azithromycin serum and tissues concentrations after intramuscular administracion in calves. Pharmacokinetics of azithromycin J. The Ciencias Veterinarias, Universidad Nacional main characteristics of azithromycin suggest that it could be useful for treating de La Plata, Buenos Aires, Argentina; bovine mastitis caused by Staphylococcus aureus.

Buenos Aires, Argentina doses of azithromycin, with a h interval. Milk and plasma concentrations were measured by microbiological assay. The MIC90 was determined in 51 S. Milk maximal concentration Cmax was 7. In plasma Cmax was 0. The mean area under the concentration vs. In this study, it was determined that the production level and the mammary health status have an influence on PK parameters of azithromycin treatments in bovine mastitis.

E-mail: noram fcv. As a consequence of the Azithromycin is a macrolide belonging to a group of semi- structural changes above mentioned, this drug is more potent synthetic antimicrobial agents called azalides which were against gram-negative bacteria than other conventional macro- derived from erythromycin by adding an endocyclic nitrogen lides such as erythromycin, while its action remains the same atom in position 9 Mulazimoglu et al. Azithromycin against Gram-positive microorganisms Retsema et al.

In formulation is not available for use in production animals. Tulkens, According to the pattern of antimicrobial Like traditional macrolides, azithromycin is capable of con- activity, azithromycin is a time-dependant antimicrobial agent centrating in phagocytic cells McConnell, where it with prolonged persistent effect.

It was postulated that Ambrose et al. Lucas et al. Leukocytes, inhibition zone around the 15 lg azithromycin disk should be mainly neutrophils, macrophages and monocytes, accumulate 21—26 mm NCCLS, These animals were et al.

The animals mean may be effective for treating infections caused by Gram-positive body weight was The SCC in all cows was aerobic microorganisms which survive inside lysosomes, as the higher than , with a minimum value of and a case of S.

The milk production was The objective of this study was to investigate the azithromycin The MIC50 is the cultured for S. Milk samples were aseptically collected against the 51 S.

The range of NMC, Composite premilking samples were collected for concentrations of azithromycin used was 0. Postmilking samples were collected from each mammary quarter of all lactating cows. The first few streams were discarded and then 2—4 mL of milk was collected in sterile tubes.

Identification of S. This being the control strain for the coagulase test S. Cases exhibiting presence of five or more S. Blood samples were were considered as subclinical mastitis positive. At the same times, quarter milk samples were aseptically collected into sterile tubes. The blood samples were centrifuged at g for 15 min and the plasma Animals was transferred to sterile glass tubes.

The 51 S. The control Milk and plasma azithromycin concentrations were mea- strain for the disk-diffusion method was S. To evaluate the effect of Aires, Argentina. The reference standard was further diluted in phosphate buffer pH 8 and then separate Milk samples were aseptically collected according to the NMC standard curves for azithromycin were prepared in antimicrobial procedures NMC, Composite premilking samples were free plasma and milk working standard solutions.

Standard collected for SCC, performed with a Fossomatic electronic curves were made using azithromycin concentrations ranging cell counter Foss Electronic, Hillered, Denmark. Postmilking from 0. Standards were tested in three different occasions and bacteriological cultures. Bacteriological plotting the mean diameter of the inhibition zones against the cure was confirmed when an infected mammary quarter, of any azithromycin concentrations.

The intra-assay variation must be of the treated cows, was bacteriologically negative for S. All standard curves were linear from 0. The evaluated in composite samples at 20 days post-treatment. The plasma standard curves had correlation collected 20 and 30 days post-treatment were considered as coefficients of 0.

The limit of quantification LOQ in milk was 0. Concentrations were calculated from zone diameters using a fresh According to the interpretative criteria set by CLSI , the standard curve, which was run on the same day of the analysis.

The MIC in the S. Simultaneously, and a large AUC demonstrate major azithromycin penetration the azithromycin PK profile in plasma was determined. PK into the mammary gland. Mammary quarters were interval. Table 1. PK parameters calculated in mastitic quarters and The statistical results are shown in Table 5. There was a healthy quarters are shown in Table 2.

Experimental concentrations of azithromycin in plasma in high- Fig. Table 4. Table 5. One mammary quarter of one cow was positive at 20 and 30 days post-treatment.

Usually when running antibiograms, an Fmilk 0. Variable percentages of macrolide resistant RCmax2 0. The productive level might have strong influence on the results.

Azithro- so, the variability factors related to the used method should be mycin concentrations in PMN and alveolar cells at h after considered. Although it is not In our study, milk azithromycin concentrations were more advisable to compare MICs of different antimicrobial agents, it is than six times the S. A study made in efficacy. Therefore, further studies are necessary for a better Argentina reported an erythromycin MIC90 of 0. Pharmacokinetic parameters indi- lites.

In human, up to 10 metabolites of azithromycin have been cated a high retention of the drug in peripheral compartments. This characteristic was demonstrated by the cows Turic et al. Although the characteristics of this antimicrobial. Milk pH in the experimental animals plasma concentrations , which is a logical finding according to ranged between 6.

Previous 7. Average pH from all mastitic quarters was 7. Azi- in milk were 4. Alkaline drugs like azithromycin are trapped in acidic plasma was 0. This theoretical considerations could not, how- observed in the present work 0. Furthermore ever, be confirmed by the experimental findings reported here.

The Tmax in goats was could be explained by its very high liposolubility and penetration 1. Average plasma pH, milk pH mastitic vs.

The PK profile of this as a function of azithromycin pKa 8. After 4 and 12 h Plasma milk milk oral administration, azithromycin concentrations in PMN were 89 and times the corresponding plasma concentrations, pH 7. It is possible that a lower milk production opposite end. In the former case, the number of SCC was several times and clinical efficacy possibilities. Mastitic milk normally exhibits very According to the excellent availability obtained in milk and a high cell counts as consequence of the inflammatory reaction.

As relatively low MIC determined in vitro, we consider azithromy- it is known, azithromycin is able to reach high concentrations at cin as a potential antimastitic drug and especially an alterna- infected sites, as a result of increased delivery from phagocytes tive for the treatment of S. Nevertheless, before Wildfeuer et al.