Roxithromycin

Absorption

Very rapidly absorbed and diffused into most tissues and phagocytes.

Toxicity

Roxithromycin primarily causes gastrointestinal adverse events, such as diarrhoea, nausea, abdominal pain and vomiting. Less common adverse events include headaches, rashes, abnormal liver function values and alteration in senses of smell and taste.

Description

Roxithromycin, an oxime ether derivative of erythromycin, is a new macrolide antibiotic of high potency and long duration. Its in v i m activity spectrum is similar to that of erythromycin, but is superior to the latter against Legionella, Mycoplasma and Chlamydia.

The Uses of Roxithromycin

Roxithromycin was one of the new generation erythromycins introduced in the 1980s. Improved acid stability was achieved by converting the 9-keto group to the more stable oxime and alkylation of the oxime to provide the methoxyethoxymethyl ether oxime. In vivo, roxithromycin exhibits higher tissue levels and a longer half-life while being slightly less potent than erythromycin in vitro.

Indications

Used to treat respiratory tract, urinary and soft tissue infections.

Background

Roxithromycin is a semi-synthethic macrolide antibiotic that is structurally and pharmacologically similar to erythromycin, azithromycin, or clarithromycin. It was shown to be more effective against certain Gram-negative bacteria, particularly Legionella pneumophila. Roxithromycin exerts its antibacterial action by binding to the bacterial ribosome and interfering with bacterial protein synthesis. It is marketed in Australia as a treatment for respiratory tract, urinary and soft tissue infections.

What are the applications of Application

Roxithromycin is an antibiotic and antibacterial compound

Pharmacokinetics

Roxithromycin has the following antibacterial spectrum in vitro: Streptococcus agalactiae, Streptococcus pneumoniae (Pneumococcus), Neisseria meningitides (Meningococcus), Listeria monocytogenes, Mycoplasma pneumoniae, Chlamydia trachomatis, Ureaplasma urealyticum, Legionella pneumophila, Helicobacter (Campylobacter), Gardnerella vaginalis, Bordetella pertussis, Moraxella catarrhalis (Branhamella Catarrhalis), and Haemophilus ducreyi. Roxithromycin is highly concentrated in polymorphonuclear leukocytes and macrophages, achieving intracellular concentrations greater than those outside the cell. Roxithromycin enhances the adhesive and chemotactic functions of these cells which in the presence of infection produce phagocytosis and bacterial lysis. Roxithromycin also possesses intracellular bactericidal activity.

Metabolism

Hepatic. Roxithromycin is only partially metabolised, more than half the parent compound being excreted unchanged. Three metabolites have been identified in urine and faeces: the major metabolite is descladinose roxithromycin, with N-mono and N-di-demethyl roxithromycin as minor metabolites. The respective percentage of roxithromycin and these three metabolites is similar in urine and faeces.