Erythromycin

Oral
Prophylaxis of surgical infections
Adult: As erythromycin base or erythromycin stearate: 250-500 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. As erythromycin ethylsuccinate: 400-800 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. Doses >1 g daily should be given in more than 2 divided doses. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin base, erythromycin ethylsuccinate or erythromycin stearate: 30-50 mg/kg daily in 2-4 divided doses; may be doubled in severe infections.
Reconstitution: Powder or granules for oral susp: Reconstitute with the appropriate volume of water as indicated on the label. Invert and shake well until suspended.

Oral
Respiratory tract infections
Adult: As erythromycin base or erythromycin stearate: 250-500 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. As erythromycin ethylsuccinate: 400-800 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. Doses >1 g daily should be given in more than 2 divided doses. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin base, erythromycin ethylsuccinate or erythromycin stearate: 30-50 mg/kg daily in 2-4 divided doses; may be doubled in severe infections.
Reconstitution: Powder or granules for oral susp: Reconstitute with the appropriate volume of water as indicated on the label. Invert and shake well until suspended.

Oral
Skin and soft tissue infections
Adult: As erythromycin base or erythromycin stearate: 250-500 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. As erythromycin ethylsuccinate: 400-800 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. Doses >1 g daily should be given in more than 2 divided doses. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin base, erythromycin ethylsuccinate or erythromycin stearate: 30-50 mg/kg daily in 2-4 divided doses; may be doubled in severe infections.
Reconstitution: Powder or granules for oral susp: Reconstitute with the appropriate volume of water as indicated on the label. Invert and shake well until suspended.

Oral
Susceptible infections
Adult: As erythromycin base or erythromycin stearate: 250-500 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. As erythromycin ethylsuccinate: 400-800 mg 6-12 hourly; may be increased up to 4 g daily for severe infections. Doses >1 g daily should be given in more than 2 divided doses. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin base, erythromycin ethylsuccinate or erythromycin stearate: 30-50 mg/kg daily in 2-4 divided doses; may be doubled in severe infections.
Reconstitution: Powder or granules for oral susp: Reconstitute with the appropriate volume of water as indicated on the label. Invert and shake well until suspended.

Oral
Prophylaxis of recurrent rheumatic fever
Adult: As erythromycin base: 250 mg bid. As erythromycin ethylsuccinate: 400 mg bid.
Reconstitution: Powder or granules for oral susp: Reconstitute with the appropriate volume of water as indicated on the label. Invert and shake well until suspended.

Intravenous
Susceptible infections
Adult: As erythromycin lactobionate: 25-50 mg/kg daily or 15-20 mg/kg daily in divided doses. Max: 4 g daily. Doses may be given as continuous or via intermittent infusion over 20-60 minutes 6 hourly. Replace with oral preparation immediately. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin lactobionate: Same as adult dose.
Reconstitution: IV: Add appropriate amount of sterile water for inj to prepare a concentration of 50 mg/mL; further dilute with ≥100 mL of suitable diluent to a final concentration of 1 mg/mL (continuous infusion) or 1-5 mg/mL (intermittent infusion).

Intravenous
Respiratory tract infections
Adult: As erythromycin lactobionate: 25-50 mg/kg daily or 15-20 mg/kg daily in divided doses. Max: 4 g daily. Doses may be given as continuous or via intermittent infusion over 20-60 minutes 6 hourly. Replace with oral preparation immediately. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin lactobionate: Same as adult dose.
Reconstitution: IV: Add appropriate amount of sterile water for inj to prepare a concentration of 50 mg/mL; further dilute with ≥100 mL of suitable diluent to a final concentration of 1 mg/mL (continuous infusion) or 1-5 mg/mL (intermittent infusion).

Intravenous
Prophylaxis of surgical infections
Adult: As erythromycin lactobionate: 25-50 mg/kg daily or 15-20 mg/kg daily in divided doses. Max: 4 g daily. Doses may be given as continuous or via intermittent infusion over 20-60 minutes 6 hourly. Replace with oral preparation immediately. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin lactobionate: Same as adult dose.
Reconstitution: IV: Add appropriate amount of sterile water for inj to prepare a concentration of 50 mg/mL; further dilute with ≥100 mL of suitable diluent to a final concentration of 1 mg/mL (continuous infusion) or 1-5 mg/mL (intermittent infusion).

Intravenous
Skin and soft tissue infections
Adult: As erythromycin lactobionate: 25-50 mg/kg daily or 15-20 mg/kg daily in divided doses. Max: 4 g daily. Doses may be given as continuous or via intermittent infusion over 20-60 minutes 6 hourly. Replace with oral preparation immediately. Treatment and dosing recommendations may vary among individual products and between countries (refer to detailed product guidelines).
Child: As erythromycin lactobionate: Same as adult dose.
Reconstitution: IV: Add appropriate amount of sterile water for inj to prepare a concentration of 50 mg/mL; further dilute with ≥100 mL of suitable diluent to a final concentration of 1 mg/mL (continuous infusion) or 1-5 mg/mL (intermittent infusion).

Ophthalmic
Superficial ocular infections
Adult: As 0.5% ointment: Apply approx 1 cm length to the affected eye(s) up to 6 times daily depending on the severity of the infection.

Topical/Cutaneous
Acne vulgaris
Adult: As 2% gel: Apply onto the affected areas 1-2 times daily. Discontinue treatment if condition worsens or if there is no improvement after 6-8 weeks. As 2% solution or pads: Apply onto the affected areas bid.

Erythromycin base: Should be taken on an empty stomach. Best taken on an empty stomach at least 30 min & preferably 2 hr before meals.

Hypersensitivity. History of QT prolongation (congenital or documented acquired QT prolongation) or ventricular cardiac arrhythmia, including torsades de pointes; electrolyte disturbances (e.g. hypokalaemia, hypomagnesaemia). Concomitant use with amisulpride, astemizole, simvastatin, lovastatin, tolterodine, mizolastine, terfenadine, domperidone, pimozide, cisapride, ergotamine, dihydroergotamine, class IA (e.g. quinidine, procainamide) and class III (e.g. dofetilide, amiodarone, sotalol) antiarrhythmic agents.

Patient with CAD, severe cardiac insufficiency, conduction disturbances, clinically relevant bradycardia, myasthenia gravis. Hepatic impairment. Neonates, children, and elderly. Pregnancy and lactation. Monitoring Parameters Perform culture and susceptibility tests; consult local institutional recommendations before treatment initiation due to antibiotic resistance risks. Monitor liver and renal function (prolonged use); blood pressure, heart rate. Observe for changes in frequency of bowel movements.

Significant: Hepatic dysfunction including increased liver enzymes and/or cholestatic hepatitis, with or without jaundice; exacerbation or new onset of symptoms of myasthenia gravis; infantile hypertrophic pyloric stenosis; overgrowth of non-susceptible bacteria or fungi (prolonged or repeated therapy). Rarely, serious allergic reactions (including acute generalised exanthematous pustulosis). Blood and lymphatic system disorders: Eosinophilia. Cardiac disorders: Chest pain. Ear and labyrinth disorders: Tinnitus, deafness. Eye disorders: Mitochondrial optic neuropathy; minor ocular irritation (ophthalmic). Gastrointestinal disorders: Nausea, vomiting, diarrhoea, pancreatitis, upper abdominal pain. General disorders and administration site conditions: Fever, malaise. Topical: Application site irritation (e.g. local dryness, localised burning, erythema or tenderness, stinging of the skin). Metabolism and nutrition disorders: Anorexia. Nervous system disorders: Seizures, vertigo. Psychiatric disorders: Confusion, hallucinations. Renal and urinary disorders: Interstitial nephritis. Skin and subcutaneous tissue disorders: Pruritus, urticaria. Vascular disorders: Hypotension.
Potentially Fatal: Pseudomembranous colitis, Clostridium difficile-associated diarrhoea, QT interval prolongation, torsades de pointes, severe skin reactions (e.g. Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme), angioneurotic oedema, anaphylaxis.

Symptoms: Hearing loss, severe nausea, vomiting and diarrhoea. Management: Supportive treatment. Perform gastric lavage.

May increase serum concentration of acenocoumarol, alfentanil, bromocriptine, carbamazepine, cilostazol, ciclosporin, digoxin, dihydroergotamine, disopyramide, ergotamine, hexobarbitone, methylprednisolone, midazolam, omeprazole, phenytoin, quinidine, rifabutin, sildenafil, tacrolimus, domperidone, theophylline, tolterodine, triazolam, valproic acid, vinblastine, antifungals (e.g. ketoconazole, itraconazole, fluconazole), zopiclone. Increased serum concentration with cimetidine. Decreased serum concentration resulting in decreased effect with CYP3A4 inducers (e.g. rifampicin, phenytoin, carbamazepine, phenobarbital). Increased risk for CV events with hydroxychloroquine or chloroquine. Increased risk for rhabdomyolysis with HMG-CoA reductase inhibitors (e.g. lovastatin, simvastatin). Increased anticoagulant effects with oral anticoagulants (e.g. rivaroxaban, warfarin). May increase the pharmacological effect of triazolam, midazolam and related benzodiazepines. Increased risk for acute ergot toxicity (characterised by vasospasm and ischaemia of the CNS, extremities and other tissues) with ergotamine or dihydroergotamine. May increase serum concentrations of theophylline which may result in theophylline toxicity. Increased risk for hypotension, bradyarrhythmias, and lactic acidosis with Ca channel blockers.
Potentially Fatal: Increased risk for CV events including cardiac arrest, torsades de pointes and other ventricular arrhythmias with cisapride, terfenadine, astemizole, pimozide, class IA (e.g. quinidine, procainamide) and class III (e.g. dofetilide, amiodarone, sotalol) antiarrhythmic agents. Increased risk for colchicine toxicity with colchicine.

Decreased serum concentration resulting in decreased effect with St. John's wort.

May give a false-positive result for urinary catecholamines, 17-hydroxycorticosteroids and 17-ketosteroids.

Erythromycin inhibits protein synthesis by binding to the 50S ribosomal subunit of susceptible organisms resulting in blockage of transpeptidation.
Absorption: Variable and unreliable due to instability in gastric acid. Time to peak plasma concentration: 4 hours (as erythromycin base); 0.5-2.5 hours (as erythromycin ethylsuccinate); 3 hours (as erythromycin stearate).
Distribution: Widely distributed throughout body tissues and fluids; diffused into CSF (minimal). Crosses the placenta and enters breast milk. Volume of distribution: 0.64 L/kg. Plasma protein binding: 73-81% (as erythromycin base).
Metabolism: Partly metabolised in the liver by CYP3A4 isoenzyme via N-demethylation into inactive, unidentified metabolites.
Excretion: Mainly via faeces; urine (2-15% as unchanged drug). Elimination half-life: Approx 1.5-2.5 hours.

Intravenous: Store between 20-25°C. Ophthalmic: Store between 20-25°C. Oral: Store between 20-25°C. Topical/Cutaneous: Store between 20-25°C.

Acne Treatment Preparations / Eye Anti-Infectives & Antiseptics / Macrolides / Topical Antibiotics

D10AF02 - erythromycin ; Belongs to the class of topical antiinfective preparations used in the treatment of acne.
J01FA01 - erythromycin ; Belongs to the class of macrolides. Used in the systemic treatment of infections.
S01AA17 - erythromycin ; Belongs to the class of antibiotics. Used in the treatment of eye infections.