Azithromycin

It is an azalide antibiotic, a subclass of the macrolides. It retains the spectrum of activity of erythromycin against Gram-positive and Gram-negative pathogens and has increased activity against many Gram-negative and atypical micro-organisms. It has greater acid-stability than erythromycin and its gastrointestinal tolerance is better than that of erythromycin. It acts by interfering with microbial protein synthesis by binding to the 50 S ribosomal subunit.

Indications

Upper and lower respiratory tract infections,Skin and soft tissues infections, Urogenital infections.

Dosage

Upper and lower respiratory tract and skin and soft tissue infections : 500 mg once daily for 3 days or 500 mg once on Day 1 followed by 250 mg once daily for the next 4 days.Urogenital infections (Chlamydial) 1g as a single dose.Azithromycin should be taken 1 hr before or at least 2 hours after a meal

Contra-Indications

Hypersensitivity to azithromycin or other macrolides.

Special Precautions

Pseudomembranous colitis, impaired liver function, impaired renal function, antacids, containing aluminium and magnesium, children. Paediatrics: Reduced dose necessary. Not recommended in children below the age of 6 months. Pregnancy: Use with caution. Lactation: Use with caution. Elderly: No special problem.

Side Effects

Nausea, vomiting, abdominal pain, diarrhoea, dyspepsia, flatulence, dizziness, headache, vertigo.

Drug Interactions

Absorption reduced by food. Antacids reduce rate of absorption. Increases absorption of Digoxin and Cyclosporine.