Respiratory tract, clarithromycin

In patients allergic to penicillin, macrolides are usually indicated in mild respiratory tract infections. Zithromax contains azithromycin, which is a macrolide that may be indicated for respiratory tract infections. As opposed to clarithromycin (another macrolide), azithromycin does not present any significant clinical interaction with phenytoin. Ciproxin contains ciprofloxacin. 

First-line treatment in upper respiratory tract infections includes the use of penicillins, cephalosporins and mocrolides. Patients who are allergic to penicillins tend to be cross-sensitive to cephalosporins, so ore given mocrolides such as clarithromycin. 

Cethromycin (ABT-773) 39 (Advanced Life Sciences) had an NDA filed in October 2008 for the treatment of CAP.67 Advanced Life Sciences is also evaluating cethromycin 39 against other respiratory tract infections and in pre-clinical studies as a prophylactic treatment of anthrax post-exposure. Cethromycin 3968 70 is a semi-synthetic ketolide derivative of erythromycin 4071 originally synthesised by Abbott Laboratories,72 which like erythromycin 40, inhibits bacterial protein synthesis through binding to the peptidyl-transferase site of the bacterial 50S ribosomal subunit. Important macrolide antibiotics in clinical use today include erythromycin 40 itself, clarithromycin, azithromycin and, most recently, telithromycin (launched in 2001). 

Clarithromycin is indicated for the treatment of mild to moderate upper and lower respiratory tract infections as well as skin infections caused by susceptible strains of Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, H. influenzae, Legionella pneumophila, and Mycoplasma pneumoniae. The usual dosage is 250 to 500 mg twice a day for 7 to 14 days. 

Antimicrobials are over prescribed for exacerbations of asthma. Respiratory tract infections do cause increased airflow obstruction and hyperresponsiveness, but viral rather than bacterial pathogens are the commonest culprits. Antimicrobials should be prescribed only if there is high suspicion of a bacterial respiratory tract infection, e.g. purulent sputum. Note that macrolide antibiotics, such as erythromycin and clarithromycin, interfere with theophylline metabolism. 

Data from 20 clinical studies in 5000 patients who had taken ranitidine bismuth citrate (200, 400, or 800 mg bd) have been reported (14). The incidence of adverse events was not different from that associated with placebo and was independent of dose. The most common events (>1% of patients) were upper respiratory tract infections, constipation, diarrhea, nausea, vomiting, dizziness, and headache, the last being the only event reported by over 2% of the patients. Adverse events considered by the chnical investigator to be adverse reactions occurred with a similar frequency amongst patients given ranitidine bismuth citrate (8%), ranitidine hydrochloride (6%), and placebo (6%). The incidence of adverse reactions was greater when amoxicillin (11%) or clarithromycin (20%) were co-prescribed. 

In two women aged 37 and 69, acute and reversible tacrolimus nephrotoxicity developed after the addition of clarithromycin for an upper respiratory tract infection (76). 

Immunomodulatory effects of macrohdes have been repeatedly reported for example suppression of the release of chemotactic mediators may be important for the clinical effect of roxithromycin in patients with chronic lower respiratory tract infections (43). Both clarithromycin and azithromycin altered cytokine production in human monocytes in vitro (44). 

Tamaoki J, Takeyama K, Tagaya E, Konno K. Effect of clarithromycin on sputum production and its rheological properties in chronic respiratory tract infections. Antimicrob Agents Chemother 1995 39(8) 1688-90. 

Claforan cefotaxime, clarithromycin [ban, inn, usan] (Blaxln Klaricid ) is the 6-0-methyl derivative of erythromycin, a macrolide, and has superior pharmacokinetic properties. It can be used clinically as an oral or parenteral antibacterial to treat a wide variety of infections, including skin, soft tissue and respiratory tract infections. It is usually given to patients who are allergic to penicillin. 

Darkes MJ, Perry CM. Clarithromycin extended-release tablet a review of its use in the management of respiratory tract infections. Am J Respir Med 2003 2(2) 175-201. 

Azithromycin is a macrolide (erythromycin, clarithromycin, and azithromycin) that interferes with microbial protein synthesis. It is indicated in the following conditions. Adults treatment of infections of the respiratory tract, acute bacterial sinusitis, acute bacterial exacerbations of COPD, community-acquired pneumonia, Mycobacterium avium complex, pelvic inflammatory disease, pharyngitis/tonsilli-tis, skin and skin structure infections, and sexually transmitted diseases caused by susceptible organisms. Children treatment of acute bacterial sinusitis, acute otitis media caused by susceptible organisms, community-acquired pneumonia, pharyngitis/tonsillitis caused by S. pyogenes in patients who cannot use first-line therapy. 

Clarithromycin is an H. pylori agent/macrolide, which inhibits microbial protein synthesis. Clarithromycin is indicated in the treatment of infections of the respiratory tract, skin and skin structure treatment of disseminated atypical mycobacterial infections caused by susceptible strains of specific microorganisms and prevention of disseminated Mycobacterium avium complex disease in patients with advanced HIV infection. Clarithromycin in combination with omeprazole is indicated in the treatment of patients with an active duodenal ulcer associated with H. pylori infection. In children it is used in acute otitis media. Macrolides are erythromycin, clarithromycin, and azithromycin. 

Erythromycin has been recommended as an alternative to penicillin in allergic patients for prevention of bacterial endocarditis after dental or respiratory-tract procedures. Clindamycin has replaced erythromycin for use in penicillin-allergic patients. Clarithromycin or azithromycin as a single 500-mg dose also may be used. 

Benazzo, M., Giacopini, G., Oldini, C., Scheiber, E., Tombolini, A., and Mira, E. (1998). Flurithromycin versus clarithromycin in upper respiratory tract infections. Curr Ther Res. 59, 28-38. 

Langtry, H. D., and Brogden, R. N. (1997). Clarithromycin. A review of its efficacy in the treatment of respiratory tract infections in immunocompetent patients. Drugs 53,973-1004. 

Clarithromycin has been compared with amoxicillin suspension in the treatment of children with lower respiratory tract infections. No significant differences were seen between the groups with respect to clinical cure rates and incidence and severity of adverse events, which generally were mild [35], Five days of treatment with clarithromycin suspension was superior to 10 days of penicillin suspension in eradicating Streptococcus pyogenes in children with streptococcal pharyngitis [36]. 

Neu, H. C., and Chick, T. W. (1993). Efficacy and safety of clarithromycin compared to cefixime as outpatient treatment of lower respiratory tract infections. Chest 104, 1393-1399. 

Fong, 1. W., Laforge, J., Dubois, J., Small, D., Grossman, R., and Zakhari, R. (1995). Clarithromycin versus cefaclor in lower respiratory tract infections. The Canadian Bronchitis Study Group. Clin. Invest. Med. 18, 131-138. 

Macklin, J. L., James, I., Kearsley, N. J., and Coles, S. J. (1993). A single-blind, randomised, comparative study of clarithromycin and amoxycillin suspensions in the treatment of children with lower respiratory tract infections. J. Chemother. 5, 174-180. 

Bradbury, F. (1993). Comparison of azithromycin versus clarithromycin in the treatment of patients with lower respiratory tract infection. J. Antimicrob. Chemother. 31, 153-162. 

In clinical studies, Tamaoki and colleagues [35] examined the effect of clarithromycin on sputum production and its rheological properties in patients with chronic lower respiratory tract infections. Clarithromycin was given at 100 mg twice daily for 8 weeks and compared with placebo. They showed that clarithromycin almost halved sputum volume, and that the percent solids of the sputum increased, with no effect of placebo. Elastic modulus (O ) significantly increased (at 10 Hz), whereas dynamic viscosity (h ) remained unchanged (Fig. 9). The reduction of sputum production and the corresponding increase in... 

Schembri S, Williamson PA, Short PM, Singanayagam A, Akram A, Taylor J, et al. Cardiovascular events after clarithromycin use in lower respiratory tract infections analysis of two prospective cohort studies. BMJ 2013 346dl235. 

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