erythromycin ethylsuccinate: clinical use

Prescribing considerations

• Confirm that the infection and likely organism are suitable for a macrolide and follow applicable antimicrobial policy.
• Review all medicines for CYP3A4, P-glycoprotein and QT-related interactions.
• Assess cardiac disease, bradycardia, hepatic impairment, myasthenia gravis and previous antibiotic-associated colitis.
• In young infants, balance benefit against infantile hypertrophic pyloric stenosis risk and advise carers to report vomiting or feeding irritability.
• Check the selected suspension’s sucrose, sorbitol, sodium and flavouring content.

Contraindications and cautions

• Hypersensitivity to erythromycin or product excipients
• Known congenital or acquired QT prolongation or previous ventricular arrhythmia, including torsades de pointes
• Hypokalaemia or hypomagnesaemia
• Concomitant simvastatin, lomitapide, ergotamine or dihydroergotamine
• Concomitant medicines specifically contraindicated by the product SmPC, including domperidone, pimozide, cisapride and certain antihistamines

Monitoring

• Consider ECG and electrolyte assessment when cardiac risk factors or interacting medicines are present.
• Monitor anticoagulant effect, interacting medicine concentrations or toxicity where clinically indicated.
• Assess liver function if hepatic dysfunction is suspected and investigate jaundice or significant liver symptoms.
• Investigate severe, persistent or delayed diarrhoea for antibiotic-associated colitis.
• Review tinnitus, hearing change or vestibular symptoms, particularly where renal function is severely impaired.

Clinical pharmacology

Erythromycin ethylsuccinate is an acid-stable oral ester of erythromycin. Active erythromycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit; it is distributed widely and eliminated mainly through the liver.

Formulation and product differences

• Selected products are granules requiring reconstitution before oral use.
• Some Pinewood formulations contain sucrose and banana flavouring.
• Sugar-free Pinewood formulations contain sorbitol and orange flavouring; hereditary fructose intolerance is relevant.
• Erythroped SF formulations contain sorbitol, acesulfame potassium and banana/cream flavourings.
• Sodium and excipient content differs between products, so formulations are not automatically interchangeable for dietary or intolerance requirements.

Oral suspension

Route: Oral

Strengths: 125 mg/5 mL, 250 mg/5 mL, 500 mg/5 mL