Clarithromycin

Other approaches to inhibiting intramolecular cycli2ations of erythromycin have also proven successhil. Erom a series of O-alkyl derivatives of erythromycin, clarithromycin (6-0-methylerythromycin) (37) was selected for clinical development (146,147). Another approach replaced the C-8 proton of erythromycin with duorine, which was accompHshed by both chemical and bioconversion methods to yield durithromycin (38) (148). 

DETERMINATION OF CLARITHROMYCIN IN HUMAN PLASMA USING RP-LC WITH ELECTROCHEMICAL DETECTION... 

A selective, sensitive and stability indicating reversed phase-HPLC method was developed for the determination of clarithromycin antibiotic in human plasma. 

Liquid chromatography was performed on symmetry 5 p.m (100 X 4.6 mm i.d) column at 40°C. The mobile phase consisted of acetronitrile 0.043 M H PO (36 63, v/v) adjusted to pH 6.7 with 5 M NaOH and pumped at a flow rate of 1.2 ml/min. Detection of clarithromycin and azithromycin as an internal standard (I.S) was monitored on an electrochemical detector operated at a potential of 0.85 Volt. Each analysis required no longer than 14 min. Quantitation over the range of 0.05 - 5.0 p.g/ml was made by correlating peak area ratio of the dmg to that of the I.S versus concentration. A linear relationship was verified as indicated by a correlation coefficient, r, better than 0.999. 

Eventually, the proposed method was successfully applied to quantify clarithromycin in spiked human plasma and real samples from healthy volunteers after oral administration of the dmg indicating the utility of this method for clinical and bioavailability studies. 

Tetracyclines. It is important to give the tetracyclines on an empty stomach tetracyclines are not to be taken with dairy products (milk or cheese). The exceptions are doxycycline (Vibramycin) and minocycline (Minocin), which may be taken with dairy products or food. The nurse should give clindamycin with food or a full glass of water. The nurse can give troleandomycin and clarithromycin without regard to meals. All tetracyclines should be given with a full glass of water (240 mL). 

Mr. Park, a patient in a nursing home, has been receiving clarithromycin (Biaxin) for an upper respiratory infection for 9 days. The nurse assistant reports that he has been incontinent of feces for the past 2 days. Analyze whether this matter should be investigated. 

Systemic treatment of erythrosis finds its rationale in the association of rosacea with H. Pylori infection. The following scheme has heen suggested clarithromycin 250 mg twice daily + metronidazole 400 mg twice daily clarithrom-... 

Roxithromycin has similar in vitro activity to erythromycin but enters leucocytes and macrophages more rapidly with higher concentrations in the lysosomal component of the phagocytic cells. It is likely to become an important drug against Legionella pneumophila. Clarithromycin is also of potential value. 

Specific concomitant medications or consumptions (check specific statin package insert for warnings) fibrates (especially gemfibrozil, but other fibrates too), nicotinic acid (rarely), cyclosporine, azole antifungals such as itraconazole and ketoconazole, macrolide antibiotics such as erythromycin and clarithromycin, protease inhibitors used to treat Acquired Immune Deficiency Syndrome, nefazodone (antidepressant), verapamil, amiodarone, large quantities of grapefruit juice (usually more than 1 quart per day), and alcohol abuse (independently predisposes to myopathy)... 

Uncomplicated exacerbation Not requiring hospitalization Less than 3 exacerbations per year No comorbid illness I I V, greater than 50% predicted No recent antibiotic therapy Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis Oral Macrolide (azithromycin, clarithromycin) Second- or third-generation cephalosporin (cefuroxime, cefpodoxime, cefdinir, cefprozil) Doxycycline Ketolide (telithromycin) P-Lactam/P-Iactamase inhibitor (amoxicillin-clavulanate) Intravenous Not recommended... 

The first-line regimen should contain a PPI plus clarithromycin and either amoxicillin or metronidazole. The combination of two antimicrobials and a PPI leads to cure rates greater than 80% (by intention-to-treat basis) and reduces the... 

Amoxicillin 1 g three times a day + omeprazole 20 mg twice a day Clarithromycin 500 mg three times a day + omeprazole 40 mg every day... 

Preexisting antimicrobial resistance is an increasing cause of treatment failure and is estimated to account for up to 70% of all treatment failures. Geography is the most important factor in HP resistance. Metronidazole-resistant strains are more prevalent in Asia (85%) than North America (30%).15 Primary resistance to amoxicillin and tetracycline remains low in both the United States and Europe. Clarithromycin resistance rates are estimated to be approximately 10% in the United States. Another confounding factor when evaluating potential antibiotic resistance is that culture and sensitivity studies are not routinely performed with HP infection. 

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