Lekoklar (Clarithromycin)

Clarithromycin is a macrolide antibiotic used to treat a range of bacterial infections.

• Community‑acquired pneumonia: eradicates the causative bacteria and improves respiratory function.
• Acute bacterial sinusitis: reduces sinus inflammation and clears infection.
• Acute bacterial exacerbations of chronic bronchitis: shortens symptom duration and prevents complications.
• Skin and soft‑tissue infections: eliminates pathogenic bacteria and promotes wound healing.
• Helicobacter pylori eradication (in combination therapy): contributes to bacterial clearance as part of a multi‑drug regimen.

• Clarithromycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, blocking translocation of the peptidyl‑tRNA. This action prevents elongation of the nascent peptide chain, halting bacterial growth and leading to a bacteriostatic effect against susceptible organisms.

Clarithromycin may cause a range of adverse reactions, from mild to severe.

Common Side Effects

• Nausea: mild to moderate upset stomach.
• Diarrhea: frequent loose stools.
• Abdominal pain: cramping or discomfort.
• Altered taste: metallic or bitter sensation.
• Headache: mild to moderate.
• Vomiting: occasional episodes.

Serious or Rare Side Effects

• Severe allergic reactions: rash, swelling, anaphylaxis.
• QT interval prolongation: risk of cardiac arrhythmias.
• Hepatic dysfunction: elevated liver enzymes or hepatitis.
• Clostridioides difficile infection: severe colitis.
• Cardiac arrhythmias: ventricular tachycardia or fibrillation.
• Stevens‑Johnson syndrome: severe skin reactions.

Before initiating clarithromycin therapy, consider the following precautions.

• Assess renal and hepatic function: adjust use if impairment is present.
• Monitor cardiac status: watch for QT prolongation, especially in patients with existing heart disease.
• Use with caution in hepatic impairment: may increase drug exposure.
• Avoid in patients with known macrolide hypersensitivity: risk of severe allergic reaction.
• Review concomitant medications: potential for significant drug‑drug interactions.
• Store at ambient temperature: keep in the original pack, protect from moisture.

Clarithromycin interacts with several medicines; awareness of interaction severity guides clinical decisions.

Major Interactions (Avoid)

• Cisapride: risk of serious cardiac arrhythmias.
• Pimozide: may cause QT prolongation and ventricular arrhythmias.
• Ergot alkaloids: can precipitate ergotism.
• Colchicine: increased toxicity, especially in renal impairment.
• Simvastatin: elevated plasma levels leading to myopathy.

Moderate Interactions (Monitor Closely)

• Oral contraceptives: reduced efficacy, consider backup method.
• Digoxin: increased serum concentrations, monitor levels.
• Theophylline: heightened risk of toxicity, adjust dose if needed.
• Carbamazepine: reduced clarithromycin levels, may diminish efficacy.
• Rifampin: induces metabolism, decreasing clarithromycin exposure.