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Quick facts
- Drug class
- Macrolide [EPC], Macrolide Antimicrobial [EPC]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 197650
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
INDICATIONS AND USAGE To reduce the development of drug-resistant bacteria and maintain the effectiveness of erythromycin tablets, USP and other antibacterial drugs, erythromycin tablets, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. Erythromycin tablets, USP are indicated in the treatment of infections caused by susceptible strains of the designated microorganisms in the diseases listed below: Upper respiratory tract infections of mild to moderate degree caused by Streptococcus pyogenes ; Streptococcus pneumoniae ; Haemophilus influenzae (when used concomitantly with adequate doses of sulfonamides, since many strains of H. influenzae are not susceptible to the erythromycin concentrations ordinarily achieved). (See appropriate sulfonamide labeling for prescribing information). Lower respiratory tract infections of mild to moderate severity caused by Streptococcus pyogenes or Streptococcus pneumoniae . Listeriosis caused by Listeria monocytogenes . Respiratory tract infections due to Mycoplasma pneumoniae . Skin and skin structure infections of mild to moderate severity caused by Streptococcus pyogenes or Staphylococcus aureus (resistant staphylococci may emerge during treatment). Pertussis (whooping cough) caused by Bordetella pertussis . Erythromycin is effective in eliminating the organism from the nasopharynx of infected individuals, rendering them noninfectious. Some clinical studies suggest that erythromycin may be helpful in the prophylaxis of pertussis in exposed susceptible individuals. Diphtheria: Infections due to Corynebacterium diphtheriae , as an adjunct to antitoxin, to prevent establishment of carriers and to eradicate the organism in carriers. Erythrasma: In the treatment of infections due to Corynebacterium minutissimum . Intestinal amebiasis caused by Entamoeba histolytica (oral erythromycins only). […]
About this medicine
DESCRIPTION Erythromycin tablets, USP are an antibacterial product containing erythromycin, USP, in a unique, nonenteric film coating for oral administration. Erythromycin tablets are available in two strengths containing either 250 mg or 500 mg of erythromycin base. Erythromycin is produced by a strain of Saccharopolyspora erythraea (formerly Streptomyces erythraeus ) and belongs to the macrolide group of antibiotics. It is basic and readily forms salts with acids. Erythromycin is a white or slightly yellow powder or colorless or slightly yellow crystals, very slightly soluble to practically insoluble in water and soluble in alcohol, in chloroform and in ether. Erythromycin is known chemically as (3 R *,4 S *,5 S *,6 R *,7 R *,9 R *,11 R *,12 R *,13 S *,14 R *)-4-[(2,6-Dideoxy-3- C -methyl-3- O -methyl-α- L -ribo-hexopyranosyl)oxy]-14-ethyl-7,12,13-trihydroxy-3,5,7,9,11,13-hexamethyl-6-[[3,4,6-trideoxy-3-(dimethylamino)-β- D -xylo-hexopyranosyl]oxy]oxacyclotetradecane-2,10-dione. The molecular formula is C 37 H 67 NO 13 and the molecular weight is 733.93. The structural formula is: Inactive Ingredients Colloidal silicon dioxide, crospovidone, croscarmellose sodium, D&C red #30 aluminium lake, hydroxypropyl cellulose, hypromellose phthalate, hypromellose, iron oxide red, magnesium stearate, microcrystalline cellulose, polyethylene glycol, povidone (k-30), povidone (k-90), propylene glycol, sodium citrate dihydrate, sorbic acid, sodium hydroxide, sorbitan monooleate, titanium dioxide and talc. Additionally, each 250 mg tablets contain iron oxide yellow. Image
Who should not take it
CONTRAINDICATIONS Erythromycin is contraindicated in patients with known hypersensitivity to this antibiotic. Erythromycin is contraindicated in patients taking terfenadine, astemizole, cisapride, pimozide, ergotamine or dihydroergotamine. (See PRECAUTIONS - Drug Interactions ). Do not use erythromycin concomitantly with HMG CoA reductase inhibitors (statins) that are extensively metabolized by CYP 3A4 (lovastatin or simvastatin), due to the increased risk of myopathy, including rhabdomyolysis.
Warnings
WARNINGS Hepatotoxicity There have been reports of hepatic dysfunction, including increased liver enzymes and hepatocellular and/or cholestatic hepatitis, with or without jaundice, occurring in patients receiving oral erythromycin products. QT Prolongation Erythromycin has been associated with prolongation of the QT interval and infrequent cases of arrhythmia. Cases of torsades de pointes have been spontaneously reported during postmarketing surveillance in patients receiving erythromycin. Fatalities have been reported. Erythromycin should be avoided in patients with known prolongation of the QT interval, patients with ongoing proarrhythmic conditions such as uncorrected hypokalemia or hypomagnesemia, clinically significant bradycardia and in patients receiving Class IA (quinidine, procainamide) or Class III (dofetilide, amiodarone, sotalol) antiarrhythmic agents. Elderly patients may be more susceptible to drug-associated effects on the QT interval. Syphilis in Pregnancy There have been reports suggesting that erythromycin does not reach the fetus in adequate concentration to prevent congenital syphilis. Infants born to women treated during pregnancy with oral erythromycin for early syphilis should be treated with an appropriate penicillin regimen. Clostridium difficile Associated Diarrhea Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including erythromycin tablets and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C.difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. […]
Reported side effects
ADVERSE REACTIONS The most frequent side effects of oral erythromycin preparations are gastrointestinal and are dose-related. They include nausea, vomiting, abdominal pain, diarrhea and anorexia. Symptoms of hepatitis, hepatic dysfunction and/or abnormal liver function test results may occur (See WARNINGS ). Onset of pseudomembranous colitis symptoms may occur during or after antibacterial treatment (See WARNINGS ). Erythromycin has been associated with QT prolongation and ventricular arrhythmias, including ventricular tachycardia and torsades de pointes (See WARNINGS ). Allergic reactions ranging from urticaria to anaphylaxis have occurred. Skin reactions ranging from mild eruptions to erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis have been reported rarely. There have been reports of interstitial nephritis coincident with erythromycin use. There have been rare reports of pancreatitis and convulsions. There have been isolated reports of reversible hearing loss occurring chiefly in patients with renal insufficiency and in patients receiving high doses of erythromycin. To report SUSPECTED ADVERSE REACTIONS, contact Zydus Pharmaceuticals (USA) Inc. at 1-877-993-8779 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Interactions with other medicines
Drug Interactions Serious adverse reactions have been reported in patients taking erythromycin concomitantly with CYP3A4 substrates. These include colchicine toxicity with colchicine; rhabdomyolysis with simvastatin, lovastatin and atorvastatin; and hypotension with calcium channel blockers metabolized by CYP3A4 (e.g., verapamil, amlodipine, diltiazem) (see PRECAUTIONS - Drug Interactions ). There have been post-marketing reports of colchicine toxicity with concomitant use of erythromycin and colchicine. This interaction is potentially life-threatening and may occur while using both drugs at their recommended doses (see PRECAUTIONS - Drug Interactions ). Rhabdomyolysis with or without renal impairment has been reported in seriously ill patients receiving erythromycin concomitantly with lovastatin. Therefore, patients receiving concomitant lovastatin and erythromycin should be carefully monitored for creatine kinase (CK) and serum transaminase levels. (See package insert for lovastatin). Drug Interactions Theophylline Erythromycin use in patients who are receiving high doses of theophylline may be associated with an increase in serum theophylline levels and potential theophylline toxicity. In case of theophylline toxicity and/or elevated serum theophylline levels, the dose of theophylline should be reduced while the patient is receiving concomitant erythromycin therapy. There have been published reports suggesting that when oral erythromycin is given concurrently with theophylline there is a decrease in erythromycin serum concentrations of approximately 35%. The mechanism by which this interaction occurs is unknown. The decrease in erythromycin concentrations due to co-administration of theophylline could result in subtherapeutic concentrations of erythromycin. Hypotension, bradyarrhythmias and lactic acidosis have been observed in patients receiving concurrent verapamil, belonging to the calcium channel blockers drug class. Concomitant administration of erythromycin and digoxin has been reported to result in elevated digoxin serum levels. […]
If too much is taken
OVERDOSAGE In case of overdosage, erythromycin should be discontinued. Overdosage should be handled with the prompt elimination of unabsorbed drug and all other appropriate measures should be instituted. Erythromycin is not removed by peritoneal dialysis or hemodialysis.
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 20 March 2024. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.