Lekoklar Forte (Clarithromycin)

Clarithromycin is a macrolide antibiotic used to treat bacterial infections affecting various organ systems.

• Respiratory tract infections: effective in eradicating susceptible bacteria causing acute bronchitis, pneumonia, and related conditions.
• Sinusitis: clears bacterial involvement in acute and chronic sinus inflammation.
• Pharyngitis: resolves streptococcal and other bacterial throat infections.
• Skin and soft tissue infections: treats cellulitis, erysipelas, and other bacterial skin conditions.
• Community‑acquired pneumonia: combats typical pathogens responsible for outpatient pneumonia cases.

• Clarithromycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, blocking translocation of the peptidyl‑tRNA. This action prevents the 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: transient upset stomach occurring shortly after dosing.
• Diarrhea: loose stools that may be mild to moderate.
• Abdominal pain: cramping or discomfort in the stomach area.
• Taste disturbance: altered or metallic taste perception.
• Headache: mild to moderate headache episodes.
• Vomiting: occasional emesis, especially with higher doses.

Serious or Rare Side Effects

• Severe allergic reactions: rash, itching, swelling, or anaphylaxis.
• Clostridioides difficile‑associated diarrhea: persistent watery stools with abdominal pain.
• Liver enzyme elevation: signs of hepatic stress such as jaundice.
• QT interval prolongation: potential cardiac rhythm disturbances.
• Stevens‑Johnson syndrome: rare but serious skin and mucous membrane reaction.
• Hepatotoxicity: rare liver injury presenting with fatigue and dark urine.

Before initiating therapy with clarithromycin, clinicians should consider several safety measures.

• Assess renal function: adjust therapy if significant impairment exists.
• Monitor liver enzymes: watch for hepatotoxicity during prolonged use.
• Review cardiac history: avoid in patients with known QT prolongation or arrhythmias.
• Evaluate concomitant medications: check for drugs that may interact adversely.
• Avoid in patients with documented hypersensitivity to macrolides.
• Store at ambient temperature: keep in the original container, protect from moisture and direct sunlight.

Clarithromycin interacts with several medicines; understanding the level of risk guides safe prescribing.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir): may cause toxic plasma levels.
• Certain antiarrhythmics (e.g., amiodarone): increase risk of QT prolongation.
• Simvastatin: heightened risk of myopathy and rhabdomyolysis.

Moderate Interactions (Monitor Closely)

• Warfarin: may enhance anticoagulant effect, requiring INR monitoring.
• Oral contraceptives: reduced efficacy, consider alternative contraception.
• Carbamazepine: may lower clarithromycin concentrations.
• Digoxin: increased serum levels, monitor for toxicity.
• Theophylline: possible elevation of plasma theophylline, watch for side effects.