Macrolide antibiotics dosage

The average blood concentration of a macrolide antibiotic observed in a panel of twelve adult males following oral administration of 250 mg of the antibiotic in a tablet dosage form are given below ... 

Tilmicosin is a macrolide antibiotic exclusively used in veterinary medicine and resembling tylosin. It is approved for treatment of respiratory diseases in beef cattle and sheep by the subcutaneous route (100, 101). It is also indicated for treatment and control of respiratory diseases associated with mycoplasma in broiler chickens, but not in laying hens. Of major significance is that in contrast to other macrolides, tilmicosin is not safe for use in swine since fatalities may occur at dosage as low as 20 mg/kg bw (7). 

Erythromycin is a macrolide antibiotic produced by Streptomyces erythreus. It is considered the most active macrolide for treatment of staphylococcal infections in cases of penicillin resistance. It is used parenterally at a dosage of 3-5 mg/kg bw, in intramammary form at 300 mg/quarter, and orally at 20-50 mg/kg bw. For treatment of mycoplasmal infections in poultry, an oral medication... 

Kitasamycin is a macrolide antibiotic intended for use in poultry and pigs. It is administered through the feed for the protection and treatment of chicken respiratory mycoplasmosis at a dosage of 500 mg/kg feed, and for protection and treatment of pig diarrhea at a dosage of 330 mg/kg feed. 

Josamycin is a macrolide antibiotic produced by Streptomyces narbonensis vai.josamyceticus. It is used for the prevention and treatment of chronic respiratory diseases caused by mycoplasma and gram-positive germs in chickens and pigs by the oral route via drinking water or feed at a dosage of 9-18 mg/kg bw/ day for 3-5 and up to 14 days, respectively. 

Verapamil is both a snbstrate and an inhibitor of CYP3A4, which is inhibited by clarithromycin and erythromycin. Giving these macrolide antibiotics dnring verapamil therapy is likely to rednce the first-pass metabolism of verapamil, increase its systemic availability, and impair its elimination. In patients taking this combination, verapamil should be started in a low dosage and its hemodynamic effects should be monitored closely. 

In addition to being available in a variety of dosage forms as the hydrochloride salt, ranitidine is also available us a bismuth citrate salt for use with the macrolide antibiotic clarithromycin in treating patients with an active duodenal ulcer... 

Erythromycin is a macrolide antibiotic widely used for the treatment of upper and lower respiratory tract infections. Recent reports further showed that EM and its analogues are effective for the treatment of chronic airway diseases such as DPB, bronchial asthma, and chronic sinusitis [5, 15, 32]. This effectiveness is considered to be apart from their antimicrobial actions, because they are effective at half of the recommended dosage and even in cases without concomitant infection. Its precise mechanisms, however, remain unclear. Several cytokines including IL-1, TNF-a, and IL-8 have been reported to be elevated in HALF from patients with such airway inflammatory diseases (Table II), and to be decreased... 

Bekele, L.K., Gebeyehu, G.G., 2012. Application of different analytical techniques and microbiological assays for the analysis of macrolide antibiotics from pharmaceutical dosage forms and biological matrices. ISRN Anal. Chem. 2012, 1—17. Available from http //dx.doi.org/10.5402/2012/859473. 

Factors that may decrease theophylline clearance and lead to reduced dosage requirements include advanced age, bacterial or viral pneumonia, heart failure, liver dysfunction, hypoxemia from acute decompensation, and use of drugs such as cimetidine, macrolides, and fluoroquinolone antibiotics. 

Macrolides are metabolized primarily in the liver with their metabolites excreted into bile metabolism occurs to a lesser degree in the kidneys and lungs [259, 260]. Since macrolides vary widely in their serum and tissue concentrations, half-lives, and active metabolites, knowledge of their metabolism is important for optimizing dosage schedules. Some macrolides also influence the metabolism of certain other drugs, and modified metabolic conditions such as liver disease may alter antibiotic concentrations [260-264]. Because such events can lead to toxicity from either excess antibiotic or adverse drug interactions, metabolism is examined in patients... 

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