Dose and Administration

1. IV infusion by syringe pump over 60 minutes.

	Dose
Preterm neonates:	10 mg/kg/dose 6 hourly
Term neonates: ≤7 days:	10-20 mg/kg/dose 12 hourly
Term neonates: >7 days:	10-20 mg/kg/dose 8 hourly
Infants:	10-20 mg/kg/dose 6-8 hourly

Indications

1. Suspected/proven infection with Mycoplasma pneumoniae, Ureaplasma urealyticum, and Chlamydia trachomatis.
2. As a substitute for penicillin in situations of significant hypersensitivity to penicillin.
3. Treatment for and prophylaxis against Bordetella pertussis.

Contraindications and Precautions

1. Known hypersensitivity to erythromycin or other macrolides.
2. Infants with biliary tract obstruction.
3. Caution in preterm infants, especially extreme immaturity.
4. Caution in infants with jaundice, liver dysfunction, and biliary tract disease.

Interactions

• Increase serum digoxin levels.
• Midazolam: increases effect.
• Theophylline decreases erythromycin blood levels and increases theophylline toxicity. Effect on half life of caffeine has not been clarified.
• Never give erythromycin to a baby receiving cisapride because there is a risk of arrhythmia.

Clinical Pharmacology

Bacteriostatic antibiotic which suppresses bacterial protein synthesis. The antibacterial spectrum is similar to penicillin but extended to include Mycoplasma pneumoniae, Ureaplasma urealyticum and Chlamydia trachomatis.

Vd 45% of body weight in adults. Antibacterial levels are achievable in all tissues except brain and CSF. Highly bound (64-98%) to human plasma protein. Hepatic excretion into bile as active compound. Only 5-15% of administered dose excreted in the active form in the urine. Plasma half life equals 2-4 hours.

Possible Adverse Effects

1. Venous irritation, soft tissue injury at IV injection site.
2. Pain, soft tissue injury at IM injection site. Not suitable for IM administration.
3. Gastrointestinal disturbances (nausea, vomiting, diarrhoea).
4. Jaundice, intrahepatic cholestasis.
5. Reversible hearing loss (very high doses).
6. Hypersensitivity reactions (urticaria, mild skin eruptions, anaphylaxis) rare.
7. Sudden severe bradycardia after IV administration. Prolongation of QT interval and ventricular arrhythmias with rapid IV administration.

Special Considerations

1. May antagonise action of penicillins, cephalosporins.
2. Concurrent use with theophylline, phenytoin, carbamapezine, or digoxin may be associated with elevation in serum levels of these drugs. The dose of these drugs should be reduced in infants and serum concentrations monitored closely.
3. Reduce dose of erythromycin if severe jaundice and/or hepatic dysfunction.