Ordipha (Azithromycin)

Azithromycin is a macrolide antibiotic that acts on a range of bacterial infections.

• Community‑acquired pneumonia: helps reduce bacterial load and speeds the recovery of patients.
• Uncomplicated skin and soft‑tissue infections: provides bacterial eradication leading to clinical improvement.
• Uncomplicated genital chlamydia infection: eliminates the causative organism, achieving microbiological cure.
• Acute bacterial sinusitis: shortens symptom duration and promotes resolution.
• Acute pharyngitis due to Streptococcus pyogenes: reduces symptom severity and duration.

• Azithromycin binds to the 50S subunit of bacterial ribosomes, blocking the translocation step of protein synthesis. This inhibition prevents bacterial growth and leads to a bacteriostatic effect against susceptible Gram‑positive and Gram‑negative organisms, as well as atypical pathogens.

Azithromycin may produce a range of adverse reactions, most of which are mild and reversible.

Common Side Effects

• Gastrointestinal upset: nausea, abdominal cramping and vomiting.
• Diarrhea: often mild and self‑limiting.
• Headache: transient and usually resolves without intervention.
• Taste alteration: a temporary metallic or bitter taste.
• Rash: mild erythematous skin eruption.

Serious or Rare Side Effects

• QT‑interval prolongation: may predispose to cardiac arrhythmias.
• Severe allergic reactions: anaphylaxis, angio‑edema, or Stevens‑Johnson syndrome.
• Hepatotoxicity: elevated liver enzymes or clinically apparent hepatitis.
• Clostridioides difficile infection: severe colitis following disruption of gut flora.
• Visual disturbances: rare reports of blurred vision or photophobia.

When prescribing Azithromycin, clinicians should consider several safety aspects.

• Assess renal and hepatic function: adjust dosing in patients with significant impairment.
• Review cardiac history: avoid in patients with known QT prolongation or arrhythmias.
• Evaluate for drug allergies: contraindicate if the patient has a known macrolide hypersensitivity.
• Monitor for gastrointestinal disease: use cautiously in patients with inflammatory bowel disease.
• Counsel on pregnancy and lactation: discuss potential risks and benefits with the prescriber.
• Store at ambient temperature: keep in the original container, protect from moisture and heat.

Azithromycin can interact with several medicines, affecting its safety or efficacy.

Major Interactions (Avoid)

• Antacids containing aluminum or magnesium: reduce azithromycin absorption.
• Drugs that prolong QT interval (e.g., quinidine, sotalol): increase risk of cardiac arrhythmias.
• Digoxin: may increase serum digoxin concentrations.

Moderate Interactions (Monitor Closely)

• Warfarin: may enhance anticoagulant effect, requiring INR monitoring.
• Statins (especially simvastatin): increased risk of myopathy.
• Oral contraceptives: potential reduction in contraceptive efficacy.
• Rifampicin: may lower azithromycin plasma levels.
• Cyclosporine: increased risk of nephrotoxicity.