Erythromycin information from DrugsUpdate
P - Contraindicated in pregnancy
L - Caution when used during lactation
FI - Food *
LI - Lab *
Erythromycin is a macrolide antibiotic that has an antimicrobial spectrum similar to or slightly wider than that of penicillin, and is often used for people who have an allergy to penicillins. For respiratory tract infections, it has better coverage of atypical organisms, including mycoplasma and Legionellosis. It was first marketed by Eli Lilly and Company, and it is today commonly known as EES (erythromycin ethylsuccinate, an ester prodrug that is commonly administered).
In structure, this macrocyclic compound contains a 14-membered lactone ring with ten asymmetric centers and two sugars (L-cladinose and D-desosamine), making it a compound very difficult to produce via synthetic methods.
Erythromycin is produced from a strain of the actinomycete Saccharopolyspora erythraea.
Pharmacodynamics
Pharmacokinetics
Erythromycin inhibits protein synthesis by irreversibly binding to the 50S ribosomal subunit thus blocking the transpeptidation or translocation reactions of susceptible organisms resulting in stunted cell growth.
Absorption: Variable and unreliable due to instability in GI environment; may be reduced in the presence of food (as the stearate or base). Peak plasma concentrations after 1-4 hours.
Distribution
Widely distributed into body tissues and fluids, liver and spleen (high concentrations), polymorphonuclear lymphocytes and macrophages; crosses the placenta (5-20% foetal plasma concentrations) and enters the breast milk. Protein-binding: 70-75% (as the base), 95% (as the propionate ester).
Metabolism
Hepatic (demethylation)
Excretion
Via the urine (2-5% of the oral dose, 12-15% of the IV dose); 1.5-2.5 hours (elimination half-life).
Erythromycin Indications / Erythromycin Uses
Information Not Available
Erythromycin Adverse Reactions / Erythromycin Side Effects
Rash, urticaria; nausea, vomiting, GI discomfort; ototoxicity; central neurotoxicity; agranulocytosis; arrhythmias; pancreatitis.
Potentially Fatal: Hepatotoxicity, cholestatic jaundice; raised serum transaminases; eosinophilia.
Precautions
Warnings
Hepatic function impairment with or without jaundice has occurred primarily in adults in association with erythromycin estolate administration. Symptoms include abdominal colic, fever, malaise, nausea, and vomiting. Severe abdominal pain may stimulate an abdominal surgical emergency.
Monitor
Before treating gonorrhea, patients suspected of also having syphilis should have a microscopic examination for T. pallidum (ie, immunofluorescence, darkfield) before receiving erythromycin and monthly serologic tests for at least 4 mo thereafter.
Response to therapy
Monitor patient's response to therapy.
Sensitivity tests
Review results of culture and sensitivity testing as appropriate. Ensure erythromycin is discontinued and another antimicrobial agent is started if sensitivity tests indicate the organism is resistant to erythromycin.
Topical
Assess patient's response to therapy. Be prepared to reduce frequency of application if dryness and peeling occurs. Be prepared to discontinue therapy if more severe reactions (eg, burning, allergic reaction, severe peeling, desquamation) occur.
Special Precautions
Increased risk of cholestatic hepatitis when treatment is >10 days or in patients with previous history of erythromycin usage. History of hepatic disorders; arrhythmias; prolonged QT interval; lactation. Monitor liver function. Avoid estolate in liver impairment. Caution when using lactobionate in patients with severe renal impairment. May aggravate muscle weakness in patients with myasthenia gravis.
Other Drug Interactions
May antagonise therapeutic effects lincomycin and clindamycin. Concurrent usage may lead to increased absorption of alcohol.
Potentially Fatal: May potentiate actions of neuromuscular blockers, oral anticoagulants, ciclosporin, theophylline. Terfenadine, astemizole, cisapride toxicity increased.
Other Interactions
Food Interactions
Increased absorption when taken with meals.
Dosage
Oral
Susceptible infections
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Bronchitis
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Severe campylobacter enteritis
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Pertussis
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Diphtheria
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Legionnaire's disease
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Pneumonia
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Sinusitis
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Trench fever
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Susceptible infections in penicillin-allergic patients
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Chanroid
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Chlamydial infections
Adult: 1-2 g daily, increased up to 4 g daily for severe infections. Doses >1 g should be given in more than 2 divided doses.
Child: 30-50 mg/kg daily, increased to twice the usual dose in severe cases; 2-8 yr: 1 g daily in divided doses; <2 yr: 500 mg daily in divided doses.
Renal impairment: Severe impairment: Max: 1.5 g daily.
Oral
Acne
Adult: Maintenance: 250 mg daily. Severe cases may require up to 500 mg bid.
Child: Maintenance dose: 250 mg daily, up to 500 mg bid may be used in those >12 yr. For infants with acne, 250 mg daily in 1 or 2 divided doses may be used.
Renal impairment: Severe impairment: Max dose of 1.5 g daily.
Oral
Prophylaxis against pneumococcal infections
Adult: For patients who are unable to take penicillins or sulfonamides: 250 mg bid.
Child: For patients who are unable to take penicillins or sulfonamides: 1 mth-2 yr: 125 mg bid; for older children: 250 mg bid.
Renal impairment: Adult: Severe impairment: Max: 1.5 g daily.
Oral
Prevention of streptococcal infections in patients with evidence of rheumatic fever or heart disease
Adult: For patients who are unable to take penicillins or sulfonamides: 250 mg bid.
Child: For patients who are unable to take penicillins or sulfonamides: 1 mth-2 year: 125 mg bid; for older children: 250 mg bid.
Renal impairment: Adult: Severe impairment: Max: 1.5 g daily.
Intravenous
Susceptible infections
Adult: As lactobionate: 15-20 mg/kg/day, up to 4 g/kg/day in severe infections. May be given as a continuous or 6-hrly intermittent infusion over 20-60 minutes. Replace with oral erythromycin as soon as possible.
Renal impairment: Adult: Severe impairment: Max: 1.5 g daily.
Ophthalmic
Treatment and prophylaxis of ophthalmic infections
Adult: As 0.5% ophthalmic ointment: Apply to the affected eye(s) up to 6 times daily.
Ophthalmic
Treatment and prevention of neonatal conjunctivitis
Child: and neonate: As 0.5% ophthalamic ointment: Apply approximately 1 cm in length into each of the lower conjunctival sac, up to 2-6 times daily depending on the severity of the infection.
Topical/Cutaneous
Acne
Adult: As 2% gel/solution: Apply onto affected areas 1-2 times daily. Discontinue treatment if condition worsens or if there is no improvement after 6-8 weeks of continuous usage.
Food(before/after)
Erythromycin base
Should be taken on an empty stomach. (Best taken on an empty stomach at least ½ hr & preferably 2 hr before meals.)
List of Contraindications
Erythromycin and Pregnancy
Contraindicated in pregnancy.
Category B: Either animal-reproduction studies have not demonstrated a foetal risk but there are no controlled studies in pregnant women or animal-reproduction studies have shown an adverse effect (other than a decrease in fertility) that was not confirmed in controlled studies in women in the 1st trimester (and there is no evidence of a risk in later trimesters).
Erythromycin and Lactation
Caution when used during lactation
Erythromycin and Children
Information Not Available
Erythromycin and Geriatic
Information Not Available
Erythromycin and Other Contraindications
Hypersensitivity; porphyria; hepatic impairment; pregnancy.
Storage
Intravenous
Store at 15-25°C.
Oral Susp
Refrigerate at 2-8°C.
Topical/Cutaneous
Store at 15-25°C.
Oral Susp
Refrigerate at 2-8°C.
Lab interference
Intravenous
Store at 15-25°C.
Oral Susp
Refrigerate at 2-8°C.
Topical/Cutaneous
Store at 15-25°C.
Oral Susp
Refrigerate at 2-8°C.
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