E.E.S. 400mg Tablets
It is used to treat or prevent bacterial infections.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antibiotic
Pharmacologic Class
Macrolide antibiotic
Pregnancy Category
Category B
FDA Approved
Mar 1952
DEA Schedule
Not Controlled
Overview
What is this medicine?
Erythromycin is an antibiotic that fights bacteria in your body. It works by stopping bacteria from making the proteins they need to grow. It's used to treat various bacterial infections, like those of the lungs, skin, and some sexually transmitted infections.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, take it exactly as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. You can take this medication with or without food, unless your doctor specifies otherwise. Continue taking the medication as instructed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. Dispose of any unused or expired medication. Do not flush it down the toilet or pour it down the drain unless instructed to do so. If you have questions about the proper disposal of your medication, consult your pharmacist. You may also want to check if there are any drug take-back programs available in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To get the most benefit from your medication, take it exactly as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. You can take this medication with or without food, unless your doctor specifies otherwise. Continue taking the medication as instructed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. Dispose of any unused or expired medication. Do not flush it down the toilet or pour it down the drain unless instructed to do so. If you have questions about the proper disposal of your medication, consult your pharmacist. You may also want to check if there are any drug take-back programs available in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take the medication exactly as prescribed by your doctor, even if you start feeling better. Do not skip doses or stop taking it early, as this can lead to antibiotic resistance.
- E.E.S. (erythromycin ethylsuccinate) can be taken with or without food, but taking it with food may help reduce stomach upset.
- Avoid taking antacids containing aluminum or magnesium at the same time as erythromycin, as they can reduce its absorption. Separate by at least 2 hours.
- Avoid grapefruit juice while taking this medication, as it can increase erythromycin levels and side effects.
- Stay hydrated by drinking plenty of fluids.
- If you are taking birth control pills, discuss with your doctor if additional contraceptive methods are needed, as antibiotics can theoretically reduce their effectiveness (though this is generally considered a low risk for erythromycin).
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
400 mg (as ethylsuccinate) orally every 6 hours or 800 mg orally every 12 hours
Dose Range:
1600 - 4000 mg
Condition-Specific Dosing:
Mild to moderate infections:
400 mg every 6 hours or 800 mg every 12 hours
Severe infections:
Up to 4 g per day in divided doses
Streptococcal infections (pharyngitis):
400 mg every 6 hours for 10 days
Chlamydia trachomatis (uncomplicated urethral, endocervical, rectal infections):
800 mg three times a day for 7 days
Legionnaires' disease:
400 mg to 1 g every 6 hours
Pediatric Dosing
Neonatal:
Not established for routine use; specific indications (e.g., pertussis prophylaxis) may use 40-50 mg/kg/day in divided doses.
Infant:
30-50 mg/kg/day (as ethylsuccinate) in equally divided doses every 6 hours. For severe infections, up to 100 mg/kg/day.
Child:
30-50 mg/kg/day (as ethylsuccinate) in equally divided doses every 6 hours. For severe infections, up to 100 mg/kg/day (max 4g/day).
Adolescent:
Same as adult dosing, typically 400 mg every 6 hours or 800 mg every 12 hours.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed
Moderate:
No adjustment needed
Severe:
No adjustment needed for most patients; for very severe impairment (CrCl <10 mL/min) and high doses, consider dose reduction or increased dosing interval.
Dialysis:
Not significantly removed by hemodialysis or peritoneal dialysis. No supplemental dose needed after dialysis.
Hepatic Impairment:
Mild:
Use with caution
Moderate:
Use with caution; dose reduction may be necessary. Monitor liver function.
Severe:
Use with caution; dose reduction is likely necessary. Monitor liver function closely.
Pharmacology
Mechanism of Action
Erythromycin inhibits bacterial protein synthesis by reversibly binding to the 50S ribosomal subunit of susceptible microorganisms. This binding prevents the translocation of peptidyl tRNA, thereby inhibiting polypeptide synthesis and bacterial growth. It is generally considered bacteriostatic but can be bactericidal at high concentrations against highly susceptible organisms.
Pharmacokinetics
Absorption:
Bioavailability:
Variable (Erythromycin ethylsuccinate is an ester, which is acid-stable and better absorbed than erythromycin base, but still variable, typically 18-45%)
Tmax:
2-4 hours
FoodEffect:
Erythromycin ethylsuccinate absorption is generally enhanced by food, unlike erythromycin base which is reduced. However, some sources suggest taking with food to reduce GI upset.
Distribution:
Vd:
0.7-0.8 L/kg
ProteinBinding:
70-90%
CnssPenetration:
Limited (poor penetration into CSF, even with inflamed meninges)
Elimination:
HalfLife:
1.5-2 hours (prolonged in severe renal impairment, but not clinically significant for most doses)
Clearance:
Not available
ExcretionRoute:
Primarily biliary/fecal (90-95%), small amount (2-5%) renal
Unchanged:
Approximately 2-5% renally excreted unchanged
Pharmacodynamics
OnsetOfAction:
Rapid
PeakEffect:
Within 2-4 hours (corresponds to Tmax)
DurationOfAction:
Dependent on dosing interval, typically maintains therapeutic levels for 6-12 hours
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction: rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Signs of liver problems: dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, vomiting, or yellow skin or eyes.
Signs of a severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis): red, swollen, blistered, or peeling skin (with or without fever), red or irritated eyes, or sores in the mouth, throat, nose, or eyes.
Difficulty urinating or changes in urine output.
Severe dizziness or fainting.
Rapid heartbeat.
Abnormal heartbeat (long QT on ECG), which can be life-threatening. This risk may increase when taking other medications with this drug. Seek medical help immediately if you experience an irregular heartbeat.
Diarrhea, particularly if it is severe, bloody, or watery, as it may be a sign of a potentially life-threatening condition called C. diff-associated diarrhea (CDAD). CDAD can occur during or after antibiotic treatment.
Hearing loss, which is rare but may be more likely if you have kidney problems or take high doses of this medication.
Common and Less Severe Side Effects
Most people experience no side effects or only mild ones. However, if you notice any of the following side effects and they bother you or persist, contact your doctor:
Diarrhea
Stomach pain
Upset stomach
Vomiting
Decreased appetite
Reporting Side Effects
This is not an exhaustive list of potential side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction: rash, hives, itching, red, swollen, blistered, or peeling skin (with or without fever), wheezing, tightness in the chest or throat, trouble breathing, swallowing, or talking, unusual hoarseness, or swelling of the mouth, face, lips, tongue, or throat.
Signs of liver problems: dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, vomiting, or yellow skin or eyes.
Signs of a severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis): red, swollen, blistered, or peeling skin (with or without fever), red or irritated eyes, or sores in the mouth, throat, nose, or eyes.
Difficulty urinating or changes in urine output.
Severe dizziness or fainting.
Rapid heartbeat.
Abnormal heartbeat (long QT on ECG), which can be life-threatening. This risk may increase when taking other medications with this drug. Seek medical help immediately if you experience an irregular heartbeat.
Diarrhea, particularly if it is severe, bloody, or watery, as it may be a sign of a potentially life-threatening condition called C. diff-associated diarrhea (CDAD). CDAD can occur during or after antibiotic treatment.
Hearing loss, which is rare but may be more likely if you have kidney problems or take high doses of this medication.
Common and Less Severe Side Effects
Most people experience no side effects or only mild ones. However, if you notice any of the following side effects and they bother you or persist, contact your doctor:
Diarrhea
Stomach pain
Upset stomach
Vomiting
Decreased appetite
Reporting Side Effects
This is not an exhaustive list of potential side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe or persistent diarrhea (especially if bloody or watery, which could indicate C. difficile infection)
- Yellowing of the skin or eyes (jaundice)
- Dark urine or pale stools
- Severe stomach pain or cramping
- Unusual tiredness or weakness
- Hearing loss or ringing in the ears (tinnitus)
- Chest pain, palpitations, or irregular heartbeat
- Dizziness or fainting spells
- Signs of an allergic reaction (rash, itching, swelling of face/tongue/throat, severe dizziness, trouble breathing)
- Unexplained muscle pain, tenderness, or weakness (especially if taking a statin)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ Abnormal heart rhythms, such as a prolonged QTc interval on an electrocardiogram (ECG)
+ Other irregular heartbeats
+ Slow heartbeat
+ Low potassium or magnesium levels
Additionally, tell your doctor about all the medications you are taking, including:
Prescription and over-the-counter (OTC) drugs
Natural products
* Vitamins
This is crucial because some medications, such as those used to treat mood disorders, abnormal heart rhythms, or migraine headaches, may interact with this medication and should not be taken together.
It is not possible to list all the medications and health conditions that may interact with this drug. Therefore, it is vital to discuss all your medications and health problems with your doctor and pharmacist to ensure safe use.
Do not start, stop, or change the dose of any medication without first consulting your doctor to confirm that it is safe to do so with this medication.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
Certain health conditions, including:
+ Abnormal heart rhythms, such as a prolonged QTc interval on an electrocardiogram (ECG)
+ Other irregular heartbeats
+ Slow heartbeat
+ Low potassium or magnesium levels
Additionally, tell your doctor about all the medications you are taking, including:
Prescription and over-the-counter (OTC) drugs
Natural products
* Vitamins
This is crucial because some medications, such as those used to treat mood disorders, abnormal heart rhythms, or migraine headaches, may interact with this medication and should not be taken together.
It is not possible to list all the medications and health conditions that may interact with this drug. Therefore, it is vital to discuss all your medications and health problems with your doctor and pharmacist to ensure safe use.
Do not start, stop, or change the dose of any medication without first consulting your doctor to confirm that it is safe to do so with this medication.
Precautions & Cautions
Important Warnings and Cautions for Patients Taking This Medication
If you are taking this medication, it is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, about your treatment. This will help ensure that you receive proper care and avoid any potential interactions or complications.
Long-Term Use and Blood Work
If you are taking this medication for an extended period, your doctor may recommend regular blood tests to monitor your condition. Be sure to discuss this with your doctor to determine the best course of action for your care.
Lab Tests and Interactions
This medication may affect the results of certain lab tests. To ensure accurate test results, inform all your healthcare providers and lab workers that you are taking this medication.
Duration of Use
Do not take this medication for longer than prescribed by your doctor. Prolonged use may increase the risk of a second infection.
Dietary Considerations
If you are on a low-sodium or sodium-free diet, consult with your doctor before taking this medication, as some products may contain sodium.
Myasthenia Gravis
If you have myasthenia gravis, discuss your treatment with your doctor. Call your doctor immediately if your symptoms worsen. Additionally, be aware that this medication may cause symptoms of myasthenia gravis in people who do not have the condition. Seek medical attention right away if you experience new or worsening muscle weakness, difficulty chewing or swallowing, breathing problems, droopy eyelids, or changes in vision, such as blurred vision or double vision.
Age-Related Precautions
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor to determine the best course of action for you and your baby.
Newborns
In rare cases, newborns taking this medication may develop a severe stomach problem. If your child vomits or becomes irritable during feeding, call your doctor immediately.
If you are taking this medication, it is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, about your treatment. This will help ensure that you receive proper care and avoid any potential interactions or complications.
Long-Term Use and Blood Work
If you are taking this medication for an extended period, your doctor may recommend regular blood tests to monitor your condition. Be sure to discuss this with your doctor to determine the best course of action for your care.
Lab Tests and Interactions
This medication may affect the results of certain lab tests. To ensure accurate test results, inform all your healthcare providers and lab workers that you are taking this medication.
Duration of Use
Do not take this medication for longer than prescribed by your doctor. Prolonged use may increase the risk of a second infection.
Dietary Considerations
If you are on a low-sodium or sodium-free diet, consult with your doctor before taking this medication, as some products may contain sodium.
Myasthenia Gravis
If you have myasthenia gravis, discuss your treatment with your doctor. Call your doctor immediately if your symptoms worsen. Additionally, be aware that this medication may cause symptoms of myasthenia gravis in people who do not have the condition. Seek medical attention right away if you experience new or worsening muscle weakness, difficulty chewing or swallowing, breathing problems, droopy eyelids, or changes in vision, such as blurred vision or double vision.
Age-Related Precautions
If you are 65 or older, use this medication with caution, as you may be more susceptible to side effects.
Pregnancy and Breastfeeding
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor to determine the best course of action for you and your baby.
Newborns
In rare cases, newborns taking this medication may develop a severe stomach problem. If your child vomits or becomes irritable during feeding, call your doctor immediately.
Overdose Information
Overdose Symptoms:
- Severe nausea
- Vomiting
- Diarrhea
- Abdominal pain
- Hearing loss (reversible)
- Cholestatic hepatitis (rare)
What to Do:
Seek immediate medical attention or call a poison control center (1-800-222-1222). Treatment is supportive and symptomatic. Gastric lavage may be considered if ingestion is recent.
Drug Interactions
Contraindicated Interactions
- Colchicine (in patients with renal or hepatic impairment)
- Lurasidone
- Pimozide
- Ergotamine, Dihydroergotamine (risk of acute ergot toxicity)
- Lovastatin, Simvastatin (risk of rhabdomyolysis)
- Midazolam (oral)
- Triazolam
Major Interactions
- Amiodarone (QT prolongation, Torsades de Pointes)
- Amlodipine (increased amlodipine levels)
- Apixaban (increased apixaban levels)
- Atorvastatin (increased statin levels, rhabdomyolysis)
- Carbamazepine (increased carbamazepine levels, toxicity)
- Cisapride (QT prolongation, Torsades de Pointes)
- Clarithromycin (additive QT prolongation)
- Cyclosporine (increased cyclosporine levels, nephrotoxicity)
- Digoxin (increased digoxin levels, toxicity)
- Dofetilide (QT prolongation, Torsades de Pointes)
- Fentanyl (increased fentanyl levels, respiratory depression)
- Flibanserin (increased flibanserin levels, hypotension, syncope)
- Ivabradine (increased ivabradine levels, bradycardia)
- Phenytoin (increased phenytoin levels)
- Quinidine (QT prolongation, Torsades de Pointes)
- Ranolazine (increased ranolazine levels, QT prolongation)
- Rivaroxaban (increased rivaroxaban levels)
- Sildenafil (increased sildenafil levels)
- Tacrolimus (increased tacrolimus levels, nephrotoxicity)
- Theophylline (increased theophylline levels, toxicity)
- Tolterodine (increased tolterodine levels, QT prolongation)
- Verapamil (increased verapamil levels)
- Warfarin (increased INR, bleeding risk)
Moderate Interactions
- Alprazolam
- Buspirone
- Caffeine
- Cilostazol
- Corticosteroids (e.g., methylprednisolone)
- Dabigatran
- Eplerenone
- Esomeprazole
- Felodipine
- Ibrutinib
- Irinotecan
- Lidocaine (systemic)
- Omeprazole
- Quetiapine
- Ritonavir
- Saxagliptin
- Ticagrelor
- Tofacitinib
- Zolpidem
Minor Interactions
- Acetaminophen (minor effect on metabolism)
- Oral contraceptives (theoretical risk of reduced efficacy, but generally not clinically significant)
Monitoring
Baseline Monitoring
Liver function tests (ALT, AST, bilirubin)
Rationale: To establish baseline and identify pre-existing hepatic impairment, as erythromycin can cause cholestatic hepatitis.
Timing: Before initiating therapy, especially in patients with pre-existing liver disease.
ECG (Electrocardiogram)
Rationale: To assess baseline QT interval, especially in patients with risk factors for QT prolongation (e.g., pre-existing cardiac disease, electrolyte abnormalities, concomitant QT-prolonging drugs).
Timing: Before initiating therapy if risk factors are present.
Routine Monitoring
Liver function tests (ALT, AST, bilirubin)
Frequency: Periodically, especially with prolonged therapy (e.g., >14 days) or in patients with hepatic impairment.
Target: Within normal limits or stable relative to baseline.
Action Threshold: Significant elevation (e.g., >3x ULN) may warrant dose reduction or discontinuation.
INR (International Normalized Ratio)
Frequency: More frequently (e.g., daily or every other day) when co-administered with warfarin.
Target: Therapeutic range for indication.
Action Threshold: INR outside target range; adjust warfarin dose as needed.
Serum drug levels (e.g., theophylline, carbamazepine, digoxin, cyclosporine, tacrolimus)
Frequency: As clinically indicated, especially when co-administered with drugs with narrow therapeutic indices.
Target: Therapeutic range for the co-administered drug.
Action Threshold: Levels outside target range; adjust co-administered drug dose as needed.
ECG (QTc interval)
Frequency: Periodically, especially in patients with risk factors for QT prolongation or if new symptoms (e.g., palpitations, syncope) occur.
Target: <450 ms (men), <470 ms (women); or <500 ms in patients with pre-existing prolongation.
Action Threshold: Significant QTc prolongation (>500 ms or increase >60 ms from baseline) may warrant discontinuation or alternative therapy.
Symptom Monitoring
- Nausea
- Vomiting
- Diarrhea
- Abdominal pain
- Yellowing of skin or eyes (jaundice)
- Dark urine
- Pale stools
- Unusual fatigue
- Hearing loss or ringing in ears (tinnitus)
- Palpitations
- Dizziness
- Fainting spells
- Muscle pain or weakness (especially with statins)
- Unusual bleeding or bruising (with warfarin)
Special Patient Groups
Pregnancy
Erythromycin is generally considered safe for use during pregnancy (Pregnancy Category B). Studies in animals have not shown harm to the fetus, and adequate, well-controlled studies in pregnant women have not shown a risk to the fetus in any trimester.
Trimester-Specific Risks:
First Trimester:
Low risk; no evidence of increased congenital malformations.
Second Trimester:
Low risk.
Third Trimester:
Low risk.
Lactation
Erythromycin is excreted into breast milk in small amounts. It is generally considered compatible with breastfeeding (Lactation Risk L2 - likely compatible). Monitor the infant for potential adverse effects such as diarrhea, candidiasis (thrush, diaper rash), or allergic reaction.
Infant Risk:
Low risk; potential for mild gastrointestinal upset or alteration of gut flora in the infant.
Pediatric Use
Erythromycin is commonly used in pediatric patients for various bacterial infections. Dosing is weight-based. Caution is advised in neonates due to potential for infantile hypertrophic pyloric stenosis (IHPS), especially with erythromycin base or estolate. Erythromycin ethylsuccinate has a lower, but still present, risk. Monitor for vomiting and feeding intolerance in infants.
Geriatric Use
No specific dose adjustments are typically required based on age alone. However, elderly patients may be more susceptible to QT prolongation and hearing impairment, especially with higher doses or pre-existing conditions. Monitor for these adverse effects and drug interactions more closely.
Clinical Information
Clinical Pearls
- Erythromycin ethylsuccinate (E.E.S.) is generally better tolerated gastrointestinally than erythromycin base, and its absorption is less affected by food.
- It is a potent CYP3A4 inhibitor, leading to numerous significant drug interactions. Always review concomitant medications.
- While generally safe, be mindful of the risk of QT prolongation, especially in patients with pre-existing cardiac conditions, electrolyte imbalances, or on other QT-prolonging drugs.
- Cholestatic hepatitis is a rare but serious side effect; monitor liver function in prolonged therapy or in patients with hepatic impairment.
- Transient hearing loss can occur, particularly with high doses or in patients with renal or hepatic impairment.
- Erythromycin is an alternative for penicillin-allergic patients for susceptible infections.
- It has prokinetic properties and is sometimes used off-label for gastroparesis, though this is not its primary indication.
Alternative Therapies
- Azithromycin (another macrolide, longer half-life, less frequent dosing, fewer CYP interactions)
- Clarithromycin (another macrolide, similar spectrum, more CYP interactions than azithromycin)
- Penicillins (e.g., Amoxicillin, Penicillin V, if susceptible and no allergy)
- Cephalosporins (e.g., Cephalexin, Cefdinir)
- Tetracyclines (e.g., Doxycycline, Minocycline)
- Fluoroquinolones (e.g., Levofloxacin, Moxifloxacin, Ciprofloxacin, for specific indications)
- Clindamycin (for anaerobic infections or skin/soft tissue infections)
Cost & Coverage
Average Cost:
$15 - $50 per 30 tablets (400mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (Generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.