Claritrox Tablet Mechanism of Action

Pharmacology: Pharmacodynamics: Clarithromycin is a semisynthetic macrolide antibiotic.
Mechanism of actions: Clarithromycin binds to the 50S ribosomal subunit of the 70S ribosome of susceptible organisms, thereby inhibiting bacterial RNA-dependent protein synthesis.
Pharmacokinetics: Absorption: Well absorbed from the gastrointestinal tract; stable in gastric acid; food delays the rate, but not the extent, of absorption; bioavailability is approximately 55% in healthy volunteers.
Distribution and Elimination: Widely distributed into tissue and fluids, high concentrations found in nasal mucosa, tonsils, and lungs; concentrations in tissue are higher than those in serum because of high intracellular concentrations.
Binding to Plasma Proteins: 65 to 75%.
Biotransformation: Hepatically metabolised.
Half-life: Normal renal function: 250 mg every 12 hours: 3 to 4 hours.
500 mg every 12 hours: 5 to 7 hours.
Renal function impairment (creatinine clearance of <30 ml per minute): Approximately 22 hours.
Peak serum concentration: Clarithromycin: Steady-state: 250 mg every 12 hours: Approximately 1 mcg/mL.
500 mg every 12 hours: 2 to 3 mcg/mL.
14 - Hydroxyclarithromycin: Steady-state: 250 mg every 12 hours: Approximately 0.6 mcg/mL.
500 mg every 12 hours: Up to 1 mcg/mL.
Elimination: Renal: Approximately 20 and 30%, respectively, of the dose of 250- and 500-mg tablets given twice a day is excreted in the urine as unchanged drug. Faecal: Approximately 4% of a 250-mg dose is excreted in the faeces.
Microbiology: Clarithromycin is active in vitro against a variety of aerobic and anaerobic gram-positive and gram-negative microorganisms.
Additionally, the 14-OH clarithromycin metabolite also has clinically significant antimicrobial activity. The 14-OH clarithromycin is twice as active against Haemophilus influenzae microorganisms as the parent compound.
Clarithromycin has been shown to be active against most strains of the following microorganisms both in-vitro and in clinical infections.
Aerobic Gram-positive microorganisms: Staphylococcus aureus, Streptococcus pneumoniae and Streptococcus pyogenes.
Aerobic Gram-negative microorganisms: Haemophilus influenzae and Moraxella catarrhalis.
Other microorganisms: Mycoplasma pneumoniae and Chlamydia pneumoniae (TWAR).
Mycobacteria: Mycobacterium avium complex (MAC) consisting of: Mycobacterium avium, Mycobacterium intracellulare and Helicobacter pylori.
Clarithromycin has been shown to be active against most strains of Helicobacter pylori in-vitro and in clinical infections when combined with omeprazole, lansoprazole and amoxycillin, or ranitidine bismuth citrate.
The following in-vitro data are available, but their clinical significance is unknown.
Aerobic Gram-positive microorganisms: Streptococcus agalactiae, Streptococci (Groups C,F,G), Viridans group streptococci.
Aerobic Gram-negative microorganisms: Bordetella pertussis, Legionella pneumophila and Pasteurella multocida.
Anaerobic Gram-positive microorganisms: Clostridium perfringens, Peptococcus niger and Propionibacterium acnes.
Anaerobic Gram-negative microorganisms: Prevotella melaninogenica (formerly Bacteroides melaninogenicus).