Active ingredient: One tablet contains 500 mg of Clarithromycin.
Pharmacology: Pharmacodynamics: Clarithromycin exerts its antibacterial action by binding to the 50S ribosomal subunit of susceptible microorganisms resulting in inhibition of protein synthesis.
Clarithromycin is active in vitro against a variety of aerobic and anaerobic gram-positive and gram-negative microorganisms as well as most Mycobacterium avium complex (MAC) microorganisms.
Additionally, the 14-hydroxyclarithromycin metabolite also has clinically significant antimicrobial activity. The 14-hydroxyclarithromycin is twice as active against Haemophilus influenzae microorganisms as the parent compound. However, for Mycobacterium avium complex (MAC) isolates the 14-hydroxymetabolite is 4 to 7 times less active than clarithromycin. The clinical significance of this activity against Mycobacterium avium complex is unknown.
Pharmacokinetics: Clarithromycin is rapidly absorbed from the gastrointestinal tract, and undergoes first-pass metabolism; the bioavailability of the parent drug is about 55%. The extent of absorption is relatively unaffected by the presence of food. Peak concentrations of clarithromycin and its principal active metabolite, 14-hydroxyclarithromycin, are reported to be about 900 and 600 ng/ml, respectively after a single 250 mg dose by mouth; at steady state the same dose given every 12 hours as tablets produces peak concentrations of clarithromycin of about 1 mg/ml.
The pharmacokinetics of clarithromycin are non-linear and dose dependent; high doses may produce disproportionate increases in peak concentrations of the parent drug, due to saturation of the metabolic pathways.
Clarithromycin and its principal metabolite are widely distributed, and tissue concentrations exceed those in serum, in part because of intracellular uptake. Clarithromycin has been detected in breast milk. It is extensively metabolised in the liver, and excreted in faeces via the bile. At steady state about 20% and 30% of a 250 mg or 500 mg dose as tablets, respectively, is excreted in the urine as unchanged drug. 14-hydroxyclarithromycin as well as other metabolites are also excreted in the urine accounting for 10 to 15% of the dose. The terminal half-life of clarithromycin is reportedly about 3 to 4 hours in patients receiving 250 mg doses twice daily, and about 5 to 7 hours in those receiving 500 mg twice daily. The half-life is prolonged in renal impairment.
Treatment of infections caused by pathogens sensitive to clarithromycin.
Infections of nose-pharynx tract (tonsillitis, pharyngitis) and of paranasal sinuses.
Infections of lower respiratory tract: bronchitis, bacterial pneumonia and atypical pneumonia.
Skin infections: impetigo, erysipelas, folliculitis, furunculosis and septic wounds.
Use instruction: Clarithromycin STELLA 500 mg is administered orally and may be given without regard to meals.
Dosage: Usual doses in patients 12 years of age or older: 250 mg twice daily, increased to 500 mg twice daily if necessary in severe infection; for 7 to 14 days. Children may be given 7.5 mg/kg twice daily for 5 to 10 days.
For treatment and prophylaxis of disseminated infection due to Mycobacterium avium complex: 500 mg twice daily; for treatment, it should be given with other antimycobacterials.
For the eradication of H. pylori associated with peptic ulcer disease: 500 mg twice daily, clarithromycin is given with another antibacterial and either a proton pump inhibitor or a histamine H2-receptor antagonist, for 7 to 14 days.
In patients with severe renal impairment (creatinine clearance of less than 30 ml/minute): Dosage of clarithromycin may need to be halved.
Overdosage of clarithromycin can cause gastrointestinal symptoms such as abdominal pain, vomiting, nausea, and diarrhea.
Adverse reactions accompanying overdosage should be treated by the prompt elimination of unabsorbed drug and supportive measures. As with other macrolides, clarithromycin serum concentrations are not expected to be appreciably affected by hemodialysis or peritoneal dialysis.
Patients with known hypersensitivity to clarithromycin, erythromycin, or any other macrolide antibiotic.
Concomitant use of clarithromycin with certain drugs, including terfenadine, astemizole, cisapride and pimozide is contraindicated because such use is likely to produce substantially increased plasma concentrations of the drugs and possibly cause serious and/or life-threatening cardiotoxicity.
Concomitant use with ergot alkaloids (ergotamine, dihydroergotamine) also is contraindicated because of potentially serious toxicity.
Concomitant administration of Clarithromycin and the following drugs is contraindicated: Domperidone as this may result in QT prolongation and cardiac arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsades de pointes (see Interactions).
Prescribing clarithromycin in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.
Clarithromycin is principally excreted via the liver and kidney. Clarithromycin may be administered without dosage adjustment to patients with hepatic impairment and normal renal function. However, in the presence of severe renal impairment with or without coexisting hepatic impairment, decreased dosage or prolonged dosing intervals may be appropriate.
Concomitant use of clarithromycin and ranitidine bismuth citrate is not recommended in patients with creatinine clearance less than 25 ml/minute, and should not be used in patients with a history of acute porphyria.
As with other anti-infective agents, use of clarithromycin may result in overgrowth of nonsusceptible bacteria or fungi. If superinfection occurs, appropriate therapy should be instituted.
In the event of severe acute hypersensitivity reactions, such as anaphylaxis, severe cutaneous adverse reactions (SCARs) [e.g. Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalised exanthematous pustulosis (AGEP)]. Clarithromycin STELLA 500 mg should be discontinued immediately and appropriate treatment should be urgently initiated.
Pregnancy: Either studies in animals have revealed adverse effects on the foetus (teratogenic or embryocidal or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the foetus.
Lactation: Caution should be exercised when clarithromycin is administered to a nursing woman.
After oral administration of clarithromycin, some cases of gastrointestinal disturbances (nausea, heartburns, abdominal pain, diarrhea), headache and skin rashes have been reported.
Using macrolides, transient increases of SGOT-SGPT are possible, normally reversible after therapy withdrawal. While during clinical studies with clarithromycin, more severe problems relevant to the liver have not been experienced, it should be taken into account that with antibiotics of this family, episodes of cholestatic hepatitis can exceptionally happen.
Like with other antibiotics, during therapy with clarithromycin superinfections by resistant bacteria of fungi can rarely arise, needing administration withdrawal and adoption of suitable therapies.
Skin and subcutaneous tissue disorders:
Not known: Severe cutaneous adverse reactions (SCARs) including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) and acute generalised exanthematous pustulosis (AGEP).
Theophylline: Clarithromycin use in patients who are receiving theophylline may be associated with an increase of serum theophylline concentrations.
Carbamazepine: Concomitant administration of single doses of clarithromycin and carbamazepine has been shown to result in increased plasma concentrations of carbamazepine. Blood level monitoring of carbamazepine may be considered.
Anticoagulants: Concomitant administration of clarithromycin and oral anticoagulants may potentiate the effects of the oral anticoagulant.
Digoxin: Elevated serum concentrations of digoxin.
Terfenadine: When clarithromycin and terfenadine were coadministered, plasma concentrations of the active acid metabolite of terfenadine were threefold higher, on average, than the values observed when terfenadine was administered alone.
Ritonavir: When clarithromycin is used in patients receiving ritonavir, modification of the usual clarithromycin dosage generally is not necessary in those with normal renal function; however, the clarithromycin dosage should be reduced by 50% in patients with creatinine clearances of 30-60 ml/minute and reduced by 75% in patients with creatinine clearances less than 30 ml/minute.
Co-administration of Clarithromycin, known to inhibit CYP34, and a drug primarily metabolized by CYP34 may be associated with elevations in drug concentrations that could increase or prolong both therapeutic and adverse effects of the concomitant drug.
The following drugs or drug classes are known or suspected to be metabolized by CYP34 isozyme: Domperidone.
Protect from light. Do not store above 30°C.
Shelf-Life: 36 months from manufacturing date.
J01FA09 - clarithromycin ; Belongs to the class of macrolides. Used in the systemic treatment of infections.
FC tab 500 mg (yellow, caplet-shaped, biconvex, engraved with break line on one side and "Click on icon to see table/diagram/image
" on the other side) x 28's.