RiteMED Erythromycin Special Precautions

Cardiac Arrhythmias: Erythromycin should be used with caution in patients with a history of arrhythmias or a predisposition to QT interval prolongation. Certain medications may also increase the risk of arrhythmias (see Interactions).
Hepatic Impairment: Hepatic dysfunction including increased liver enzymes, and hepatocellular and/or cholestatic hepatitis, with or without jaundice, has been reported with erythromycin.
Since erythromycin is primarily excreted by the liver, the drug should be used with caution in patients with hepatic impairment or impaired biliary excretion or in those concomitantly receiving potentially hepatotoxic agents.
Clostridium difficile-associated diarrhea: This has been observed with the used of nearly all antibacterial agents, including erythromycin, and may range in severity from mild diarrhea to fatal colitis. It is important to consider this diagnosis in patients who present with diarrhea following administration of antibacterial agents.
Rhabdomyolysis: Rhabdomyolysis with or without renal impairment has been reported in seriously ill patients receiving erythromycin concomitantly with lovastatin. Therefore, patients receiving concomitant erythromycin and lovastatin should be monitored carefully for creatinine kinase and serum transaminase levels.
Myasthenia gravis: Erythromycin may aggravate muscle weakness in patients with myasthenia gravis.
Syphilis: There have been reports suggesting that erythromycin does not reach the fetus in adequate concentrations to prevent congenital syphillis. Infants born to women treated during pregnancy with oral erythromycin for early syphillis should be treated with an appropriate penicillin regimen.
Patients should have a serologic test for syphillis before receiving erythromycin as treatment for gonorrhea and a follow-up serologic test for syphillis after 3 months.
Other Precautions: Erythromycin has been associated with acute attacks of porphyria and is considered unsafe in porphyric patients.
There have been reports of infantile hyperthropic pyloric stenosis (IHPS) occurring in infants after erythromycin treatment (see Use in Children as follows).
Prescribing erythromycin in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.
When indicated, incision and drainage or other surgical procedures should be performed in conjunction with antibiotic treatment.
As with other antibacterial drugs, long term or repeated use may result in overgrowth of non-susceptible organisms, including fungi.
Renal Impairment: Since renal excretion is not a major route of elimination of erythromycin and prolongation of serum t_1/2 of the drug is not clinically important, dosage modification is not necessary in patients with renal impairment.
Hepatic Impairment: As erythromycin is primarily excreted by the liver, caution should be exercised when administering erythromycin to patients with hepatic impairment.
Effects on Ability to Drive and Use Machines: None reported.
Use in Children: In one cohort of 157 newborns who were given erythromycin for pertussis prophylaxis, seven neonates (5%) developed symptoms of non-bilious vomiting or irritability with feeding and were subsequently diagnosed as having IHPS requiring surgical pyloromyotomy. Since erythromycin may be used in the treatment of conditions in infants which are associated with significant mortality or morbidity (such as pertussis or Chlamydia), the benefit of erythromycin treatment needs to be weighed against the potential risk of developing IHPS. Parents should be informed to contact their physician if vomiting or irritability with feeding occurs.