Erythromycin USP


  • Antibiotic


  • Macrolide


  • Upper respiratory tract infections (S. pyogenes, S. pneumoniae, H. inlfuenzae)

  • Lower respiratory tract infections (S. pyogenes, S. pneumoniae)

  • Respiratory tract infections (Mycoplasma pneumoniae)

  • Skin infections (S. aureus, S. pyogenes)

  • Pertussis (Bordetella pertussis)

  • Diphtheria (Corynebacterium diphtheriae)

  • Erythasma (C. minutissimum)

  • Intestinal amebiasis (Entamoeba histolytica)

  • Pelvic inflammatory disease (N. gonorrhoeae)

  • Conjunctivitis (Chlamydia trachomatis)

  • Uncomplicated urethral, endocervical or rectal infections (Chlamydia trachomatis)

  • Nongonococcal urethritis (Ureaplasma urealyticum)

  • Primary syphilis (Treponema pallidum)

  • Legionnaire’s disease (Legionella pneumonphila)

  • Rheumatic fever

  • Bacterial endocarditis

  • Listeria monocytogenes infections

  • Unlabled uses: Treponema pallidum, Campylobacter jejuni, Lymphogranuloma vernereum, Calymmatobacterium granulomatis, Haemophilus ducreyi (chanchroid)


  • None


  • Pregnancy category B

  • Counsel patient to finish all medication to prevent development of resistance

  • Do not use with cisapride (ventricular arrythmias w/macrolides)

  • Urine alkalinization (pH 8.5) increases gram-negative antibacterial activity.  If needed, administer with sodium bicarbonate or other alkalinizing agent

  • Dosages are expressed in the form of erythromycin base

  • Administer IV over 20-60 minutes at intervals less than every 6 hours

Adverse Reactions (Side Effects):

  • Hypersensitivity

  • Gastrointestinal: abdominal pain (7.5%), nausea, vomiting, diarrhea (7.3%)

  • Headache (8.2%)

  • Decreased platelet count (4.8%)

  • Vaginitis

  • Local injection site irritation, DO NOT administer IV push


  • Administered by injection

  • Adult:

    • 15-20mg/kg/day administered in four equal doses (up to 4 grams per day)

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