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Erythromycin eent

Class: Antibacterials
CAS Number: 114-07-08

Medically reviewed on Jul 30, 2018


Antibacterial; macrolide antibiotic.139 140

Uses for Erythromycin

Bacterial Ophthalmic Infections

Topical treatment of superficial infections of the eye involving the conjunctiva and/or cornea caused by susceptible bacteria.139 140

Mild, acute bacterial conjunctivitis often resolves spontaneously without anti-infective treatment.135 136 137 141 Although topical ophthalmic anti-infectives may shorten time to resolution and reduce severity and risk of complications,135 136 137 141 avoid indiscriminate use of topical anti-infectives.135 141

Treatment of acute bacterial conjunctivitis generally is empiric;135 136 141 use of a broad-spectrum topical ophthalmic antibacterial usually recommended.135 136 141 In vitro staining and/or cultures of conjunctival material indicated in diagnosis and management of all cases of suspected infectious conjunctivitis in neonates,135 136 141 292 344 all cases of suspected gonococcal or chlamydial conjunctivitis,292 344 and may be indicated in management of recurrent, severe, or chronic purulent conjunctivitis or when acute conjunctivitis does not respond to initial empiric topical treatment.135 136 141

Bacterial conjunctivitis caused by Neisseria gonorrhoeae requires treatment with systemic anti-infectives (e.g., IM or IV ceftriaxone)135 136 141 292 344 with or without topical anti-infectives.135 136 141 Topical anti-infectives alone are inadequate for treatment of ophthalmia neonatorum caused by N. gonorrhoeae;292 some experts state that adjunctive use of topical anti-infectives unnecessary when appropriate systemic anti-infectives used.292

Chlamydial Ophthalmic Infections

Has been used topically in the treatment of conjunctivitis secondary to trachoma caused by Chlamydia trachomatis;127 128 129 130 131 134 136 however, systemic anti-infectives (usually oral azithromycin) are recommended for treatment of ocular trachoma.136 292

Systemic anti-infectives (e.g., oral azithromycin, doxycycline, or erythromycin) are necessary for treatment of chlamydial conjunctivitis, including chlamydial ophthalmia neonatorum.135 136 292 344 Experts state that topical anti-infectives alone are inadequate for treatment of chlamydial ophthalmic infections and are unnecessary when appropriate systemic anti-infectives used.292 344

Has been used for topical prophylaxis of ophthalmia neonatorum caused by C. trachomatis.139 140 However, efficacy of topical prophylaxis for prevention of chlamydial neonatal conjunctivitis not established.101 102 103 104 106 107 109 114 116 292 344 Experts state that erythromycin used for topical prophylaxis of gonococcal ophthalmia neonatorum will not prevent chlamydial ophthalmia neonatorum.292

Prophylaxis of Gonococcal Ophthalmia Neonatorum

Topical prophylaxis of ophthalmia neonatorum caused by N. gonorrhoeae.139 140 292 344 Efficacy for prevention of ophthalmia neonatorum caused by penicillinase-producing N. gonorrhoeae not established.139 140

CDC and AAP recommend topical erythromycin prophylaxis in all neonates as soon as possible after birth (regardless of whether they are delivered vaginally or by cesarean section);292 344 such prophylaxis required by law in most states.292 344 Although silver nitrate and tetracycline have been used in the past for topical prophylaxis of gonococcal ophthalmia neonatorum, ophthalmic preparations of these drugs no longer commercially available in the US.292 344

If erythromycin ophthalmic ointment not available, CDC recommends systemic prophylaxis with a single dose of ceftriaxone (IM or IV) for all neonates at risk for exposure to N. gonorrhoeae (especially those born to women who are at risk for gonococcal infection or received no prenatal care).344

Infants born to women with untreated gonorrhea are at high risk of infection; CDC and AAP recommend that such neonates receive systemic prophylaxis with a single dose of ceftriaxone (IM or IV) instead of topical erythromycin prophylaxis.292 344

Erythromycin Dosage and Administration


Ophthalmic Administration

Apply 0.5% ophthalmic ointment topically to the eye.139 140

For topical ophthalmic use only.139 140

Avoid contaminating tip of ointment tube with material from eye, fingers, or other source.139 140

When used for prophylaxis of gonococcal ophthalmia neonatorum, place specified amount of ointment into each of neonate’s lower conjunctival sacs139 140 and massage gently to spread ointment;292 after 1 minute, wipe away excess ointment with sterile cotton.292 Do not flush ointment from the eye following application.139 140 292 Use a new tube or single-use container of ointment for each neonate.139 140


Pediatric Patients

Bacterial Ophthalmic Infections

Apply 1-cm ribbon of 0.5% ointment to the affected eye(s) up to 6 times daily.139 140 For empiric treatment of acute bacterial conjunctivitis, experts recommend application 4 times daily for 1 week.136

Prophylaxis of Gonococcal Ophthalmia Neonatorum

Place 1-cm ribbon of 0.5% ointment into lower conjunctival sac of both eyes.139 140

Administer as soon as possible (within 1 hour) after birth.292 344 Efficacy unlikely to be affected if topical prophylaxis delayed for up to 1 hour after delivery (e.g., to facilitate parent-infant bonding);292 efficacy of prophylaxis administered after a longer delay not studied.292


Bacterial Ophthalmic Infections

Apply 1-cm ribbon of 0.5% ointment to the affected eye(s) up to 6 times daily.139 140 For empiric treatment of acute bacterial conjunctivitis, experts recommend application 4 times daily for 1 week.136

Cautions for Erythromycin


  • Hypersensitivity to erythromycin.139 140


Sensitivity Reactions


Possible sensitivity reactions.139 140

General Precautions


Prolonged use may result in overgrowth of nonsusceptible organisms, including fungi.139 140

If superinfection occurs, discontinue and institute appropriate therapy.139 140

Specific Populations


Data not available regarding use in pregnant women.139 140 Use only if clearly needed.139 140


Use with caution in nursing women.139 140

Pediatric Use

See Uses.

Geriatric Use

No overall differences in safety or efficacy compared with younger patients.140

Common Adverse Effects

Minor ocular irritation, redness, hypersensitivity.139 140

Erythromycin Pharmacokinetics



Topical application to the eye probably does not produce significant antibacterial concentrations in deep layers of cornea or in aqueous humor.a

Not known whether erythromycin is absorbed to any substantial extent from mucous membranes.a





15–25°C.139 140

Do not expose to excessive heat;140 do not freeze.140

Actions and Spectrum

  • Usually bacteriostatic; may be bactericidal in high concentrations or against highly susceptible organisms.a

  • Inhibits protein synthesis in susceptible organisms by binding to 50S ribosomal subunits.a

  • Gram-positive bacteria: Active in vitro and in clinical infections against Staphylococcus aureus (methicillin-susceptible strains only), Streptococcus pneumoniae, S. pyogenes (group A β-hemolytic streptococci; GAS), viridans streptococci (α-hemolytic streptococci), and Corynebacterium diphtheriae.139 140

  • Gram-negative bacteria: Active in vitro and in clinical infections against some strains of Haemophilus influenzae and Neisseria gonorrhoeae.139 140

  • Active against Chlamydia trachomatis and Mycoplasma pneumoniae.139 140 Also has activity against Treponema pallidum.139 140

Advice to Patients

  • Advise patients to avoid contaminating tip of ointment tube with material from the eye, fingers, or other source.139 140

  • Advise patients to immediately discontinue erythromycin ophthalmic ointment and contact a clinician at first sign of hypersensitivity reaction.139 140

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as any concomitant illnesses.139 140

  • Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.139 140

  • Importance of informing patients of other important precautionary information. (See Cautions.)139 140


Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name



Dosage Forms


Brand Names





Erythromycin Ophthalmic Ointment

AHFS DI Essentials™. © Copyright 2018, Selected Revisions July 30, 2018. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

† Use is not currently included in the labeling approved by the US Food and Drug Administration.


Only references cited for selected revisions after 1984 are available electronically.

101. Anon. Neonatal gonococcal ophthalmia—California. MMWR Morb Mortal Wkly Rep. 1983; 32:518-9.

102. Zola EM. Evaluation of drugs used in the prophylaxis of neonatal conjunctivitis. Drug Intell Clin Pharm. 1984; 18:692-6.

103. Hammerschlag MR, Chandler JW, Alexander ER et al. Erythromycin ointment for ocular prophylaxis of neonatal chlamydial infection. JAMA. 1980; 244:2291-3.

104. Rettig PJ, Patamasucon P, Siegel JD. Postnatal prophylaxis of chlamydial conjunctivitis. JAMA. 1981; 246: 2321-2.

106. Dillon HC Jr. Prevention of gonococcal ophthalmia neonatorum. N Engl J Med. 1986; 315:1414-5.

107. Sandstrom I. Ophthalmia neonatorum with special reference to Chlamydia trachomatis: diagnosis and treatment. Acta Paediatr Scand. 1986; 330:3-27.

109. Hammerschlag MR. Neonatal ocular prophylaxis. Pediatr Infect Dis J. 1988; 7:81-2.

114. Fransen L, Klauss V. Neonatal ophthalmia in the developing world: epidemiology, etiology, management and control. Int Ophthalmol. 1988; 11:189-96.

116. Bell TA, Sandstrom KI, Gravett MG et al. Comparison of ophthalmic silver nitrate solution and erythromycin ointment for prevention of natally acquired Chlamydia trachomatis. Sex Transm Dis. 1987; 14:195-200.

122. Rowe DS, Aicardi EZ, Dawson CR et al. Purulent ocular discharge in neonates: significance of chlamydia trachomatis. Pediatrics. 1979; 63:628-32.

127. Roy FH. Trachoma. Ann Ophthalmol. 1974; 6:1167-71.

128. Vastine DW, Dawson CR, Daghfous T et al. Severe endemic trachoma in Tunisia: I. Effect of topical chemotherapy on conjunctivitis and ocular bacteria. Br J Ophthalmol. 1974; 58:833-42.

129. Maichuk YF. Some aspects of rational trachoma therapy. Am J Ophthalmol. 1972; 74:684-703.

130. Dawson CR, Daghfous T, Whitcher J et al. Intermittent trachoma chemotherapy: a controlled trial of topical tetracycline or erythromycin. Bull World Health Organ. 1981; 59:91-7.

131. Dawson CR, Daghfous T, Messadi M et al. Severe endemic trachoma in Tunisia. II. A controlled therapy trial of topically applied chlortetracycline and erythromycin. Arch Ophthalmol. 1974; 92:198-203.

134. Dawson CR, Schachter J. Strategies for treatment and control of blinding trachoma: cost-effectiveness of topical or systemic antibiotics. Rev Infect Dis. 1985; 7:768-73.

135. American Academy of Ophthalmology. Preferred practice pattern (PPP) guidelines: conjunctivitis PPP - 2013. From American Academy of Ophthalmology website. Accessed 20 Dec 2017.

136. Azari AA, Barney NP. Conjunctivitis: a systematic review of diagnosis and treatment. JAMA. 2013; 310:1721-9.

137. Sheikh A, Hurwitz B, van Schayck CP et al. Antibiotics versus placebo for acute bacterial conjunctivitis. Cochrane Database Syst Rev. 2012; :CD001211.

139. Bausch & Lomb Inc. Erythromycin ophthalmic ointment, USP 0.5% prescribing information. Bridgewater, NJ; 2016 Jul.

140. Akorn, Inc. Erythromycin ophthalmic ointment USP, 0.5% prescribing information. Lake Forest, IL; 2016 Jun.

141. Barnes SD, Kumar NM, Pavin-Langston D et al. Microbial Conjunctivitis. In: Bennett JE, Dolin R, and Blaser MJ, eds. Mandell, Douglas, and Bennett's principles and practices of infectious diseases. 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:1392-1401.

292. Committee on Infectious Diseases, American Academy of Pediatrics. Report of the Committee on Infectious Diseases. 30th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2015.

344. Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines 2015. MMWR Morb Mortal Wkly Rep. 2015; 64(No. RR-3):1-135.

a. AHFS Drug Information 2018. McEvoy GK, ed. Erythromycin (ophthalmic ointment). Bethesda, MD: American Society of Health-System Pharmacists.