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Erythromycin Base
Oral, ophthalmic ointment, topical dermatologic solution for acne, topical dermatologic ointment: AK-Mycin, Akne-mycin, A/T/S, E-Mycin, Eryc, Eryderm, Erymax, Ery-Tab, Ilotycin, Ilotycin Ophthalmic, Robimycin, Staticin, T-Stat erythromycin estolate

Oral: Ilosone erythromycin ethylsuccinate

Oral: E.E.S., E-Mycin, EryPed
erythromycin gluceptate

Parenteral, IV: Ilotycin Gluceptate
erythromycin lactobionate, erythromycin stearate

Oral: Eramycin

Pregnancy Category B

Drug classes


Mechanism of action
Bacteriostatic or bactericidal in susceptible bacteria; binds to cell membrane, causing change in protein function, leading to cell death.


Systemic Administration

  • Acute infections caused by sensitive strains of Streptococcus pneumoniae, Mycoplasma pneumoniae, Listeria monocytogenes, Legionella pneumophila
  • URIs, LRIs, skin and soft-tissue infections caused by group A beta-hemolytic streptococci when oral treatment is preferred to injectable benzathine penicillin
  • PID caused by N. gonorrhoeae in patients allergic to penicillin
  • In conjunction with sulfonamides in URIs caused by Haemophilus influenzae
  • As an adjunct to antitoxin in infections caused by Corynebacterium diphtheriae and Corynebacterium minutissimum
  • Prophylaxis against alpha-hemolytic streptococcal endocarditis before dental or other procedures in patients allergic to penicillin who have valvular heart disease

Oral Erythromycin

  • Treatment of intestinal amebiasis caused by Entamoeba histolytica; infections in the newborn and in pregnancy that are caused by Chlamydia trachomatis and in adult chlamydial infections when tetracycline cannot be used; primary syphilis (Treponema pallidum) in penicillin-allergic patients; eliminating Bordetella pertussis organisms from the nasopharynx of infected individuals and as prophylaxis in exposed and susceptible individuals.
  • Unlabeled uses: erythromycin base is used with neomycin before colorectal surgery to reduce wound infection; treatment of severe diarrhea associated with Campylobacter enteritis or enterococolitis; treatment of genital, inguinal, or anorectal lymphogranuloma venereum infection;
    treatment of Haemophilus ducreyi (chancroid)

Ophthalmic Ointment

  • Treatment of superficial ocular infections caused by susceptible strains of microorganisms; prophylaxos of ophthalmia neonatorum caused by N. gonorrhoeae or C. trachomatis

Topical Dermatologic Solutions for Acne

  • Treatment of acne vulgaris
  • Topical Dermatologic Ointment
  • Prophylaxis against infection in minor skin abrasions
  • Treatment of skin infections caused by sensitive microorganisms


Systemic Administration

  • Contraindicated in the presence of allergy to erythromycin.
  • Use caution in the presence of hepatic dysfunction, lactation (secreted and may be concentrated in breast milk; may modify bowel flora of nursing infant and interfere with fever workups).

Ophthalmic Ointment

  • Contraindicated in the presence of allergy to erythromycin; viral, fungal, mycobacterial infections of the eye.

Adverse effects 

Systemic Administrations

  • CNS: Reversible hearing loss, confusion, uncontrollable emotions, abnormal thinking
  • GI: Abdominal cramping, anorexia, diarrhea, vomiting, pseudomembranous colitis, hepatotoxicity
    Hypersensitivity: Allergic reactions ranging from rash to anaphylaxis
  • Other: Superinfections

Ophthalmic Ointment

  • Dermatologic: Edema, utricaria, dermatitis, angioneurotic edema
  • Local: Irritation, burning, itching at site of application

Topical Dermatologic Preparations

  • Local: Superinfections, particularly with long-term use

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