Erythromycin

Erythromycin

Erythromycin, a powerful antibiotic, is a bacteriostatic medication. It treats numerous bacterial infections, from simple throat pain to more complex respiratory issues. 

What is Erythromycin?

Erythromycin is a bacteriostatic antibiotic drug produced by a strain of Saccharopolyspora erythraea. It belongs to the macrolide group of antibiotics (including azithromycin, clarithromycin, and spiramycin).

Erythromycin is widely helpful in treating infections caused by both gram-positive and gram-negative bacteria. It is effective against various respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease, and syphilis.

Erythromycin is available in various forms, like tablets, capsules, oral suspensions, ophthalmic solutions, ointments, gels, and injections.

Erythromycin Uses

Erythromycin is a versatile antibiotic with many applications in treating various bacterial infections. This medication is extensively used in combating respiratory infections like community-acquired pneumonia, Legionnaires disease, bronchitis, and pertussis (whooping cough). It is also effective against infections of the throat, such as diphtheria, and sexually transmitted diseases like syphilis.

Additionally, erythromycin finds use in treating:

• Skin and Soft Tissue Infections: Erythromycin can treat skin and soft tissue infections caused by susceptible bacteria. It becomes an effective acne treatment when used with topical agents like tretinoin cream or benzoyl peroxide.
• Gastrointestinal Infections: Erythromycin is FDA-approved for treating intestinal amebiasis, an infection caused by the parasite Entamoeba histolytica.
• Other Bacterial Infections: Antibiotic erythromycin helps treat ear infections, gynaecological infections, urinary tract infections, and certain types of pelvic inflammatory disease (PID).
• Prophylactic Use: Erythromycin can be used to prevent neonatal conjunctivitis in newborns and to prevent heart infections in individuals undergoing dental or other procedures.

How to Use Erythromycin

• Taking Erythromycin Tablets or Capsules: Take erythromycin only as directed by your doctor. Do not take more or less of it, do not take it more frequently, and do not take it longer than prescribed. Swallow the erythromycin tablets or capsules whole with a drink of water. Do not chew or break them.
• Taking Erythromycin Liquid: Erythromycin suspension usually comes with a syringe or spoon to help measure the correct dose. To ensure you take the right amount, use the provided syringe or spoon, not a kitchen teaspoon. Shake the liquid bottle well before each use.
• Timing of Doses: Try to space erythromycin doses evenly throughout the day. For best results, take this medication every day at the same time(s).
• Food Intake: Generally, taking erythromycin with food is better to prevent stomach upset.
• Completing the Course: You must keep taking erythromycin for the entire duration of treatment, even if you or your child start feeling better after a few doses. Stopping the treatment in between may cause the infection to return.

Side Effects of Erythromycin Tablet

The side effects of erythromycin can range from mild to rare and severe:

• Common Side Effects:
  • Nausea and vomiting
  • Diarrhoea and stomach cramps
  • Loss of Appetite
  • Bloating and Indigestion.
• Serious Side Effects (rare):
  • A skin rash
  • Severe stomach pain
  • Yellowing of the whites of the eyes or the skin or pale stool with dark urine 
  • Hallucinations
  • Tinnitus or temporary hearing loss 
  • Feeling unsteady on your feet
  • Fever
• Immediate Action Required if:
  • You or your child has had a seizure or fit
  • You have chest pains, or abnormal rhythm
  • Serious allergic reaction, like sudden swelling of the lips, mouth, throat, or tongue 
  • Shallow breathing or difficulty breathing 
  • Difficulty swallowing
  • Suddenly feeling confused, drowsy, or dizzy
  • Someone faints 

Precautions

It would help if you took certain precautions when using erythromycin to ensure its safe and effective use, such as:

• Do not take erythromycin if you have a known hypersensitivity or allergy to this drug or any other macrolide antibiotic.
• Use erythromycin with caution if you have impaired liver or kidney function.
• If you have experienced severe rashes or similar symptoms with erythromycin in the past, avoid future use of the drug.
• If you have a history of myasthenia gravis (a muscle disease) 
• Inform your doctor if you plan to receive any immunizations.
• Discuss your use of erythromycin with your doctor or dentist before undergoing surgery.
• Some erythromycin products may contain sodium, which can be problematic if you are on a salt-restricted diet or have conditions like heart failure.
• Elderlies are at higher risk of getting side effects like hearing loss and QT prolongation.
• If you are pregnant or breastfeeding

How Erythromycin Works

Erythromycin is a bacteriostatic antibiotic. This means it prevents bacteria from growing rather than directly destroying them. This action occurs by inhibiting protein synthesis. Erythromycin binds to the 23S ribosomal RNA in the 50S subunit of the bacterial ribosome. This causes a blockage in peptide chain synthesis, ultimately inhibiting protein synthesis. Humans have the 40S and 60S subunits and do not have 50S subunits, so erythromycin does not affect protein synthesis in human tissues.

Erythromycin is active against gram-positive, gram-negative, and several other organisms. The gramme-positive bacteria include Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Listeria monocytogenes, Corynebacterium minutissimum, and Corynebacterium diphtheria. The gram-negative bacteria include Legionella pneumophila, Neisseria gonorrhoeae, Haemophilus influenzae, and Bordetella pertussis. Other microorganisms covered by erythromycin include Chlamydia trachomatis, Mycoplasma pneumoniae, Entamoeba histolytica, Treponema pallidum, and Ureaplasma urealyticum.

Sometimes, resistance can develop against erythromycin.

Pro-motility Action: Aside from being a bacteriostatic macrolide antibiotic, erythromycin also works as a pro-motility drug. It stimulates smooth muscle contractions to enhance gastric emptying.

Drug Interactions

Erythromycin can interact with various medications, foods, and even grapefruit juice. The following are some of the most frequently checked interactions:

• Medications:
  • Lorazepam
  • Amoxicillin-clavulanate
  • Sulfamethoxazole-trimethoprim
  • Diphenhydramine
  • Loratadine
  • Duloxetine
  • Fluticasone nasal
  • Furosemide
  • Atorvastatin
  • Pregabalin
  • Esomeprazole
  • Acetaminophen
  • Promethazine
  • Omeprazole
  • Pantoprazole
  • Fluoxetine
  • Metoclopramide
  • Montelukast
  • Budesonide-formoterol
  • Levothyroxine
  • Topiramate
  • Acetaminophen
  • Vitamin B12 (cyanocobalamin)
  • Vitamin C (ascorbic acid)
  • Vitamin D3 (cholecalciferol)
  • Alprazolam
  • Ondansetron
  • Sertraline
  • Cetirizine
• Food Interactions:
  • Erythromycin can also interact with certain foods. Food decreases the erythromycin levels in your body, so it's recommended to take erythromycin on an empty stomach at least half an hour before or two hours after a meal. This will help your body absorb the medication more effectively.
• Grapefruit Juice Interaction:
  • Grapefruit and grapefruit juice may increase erythromycin levels in the body. Therefore, to be safe, consult your doctor before consuming grapefruit products in your diet.
• Alcohol Interaction:
  • Drinking alcohol while taking erythromycin may reduce the effectiveness of the antibiotic. 

Dosing Information

Adult Dosing

• Dosing Forms & Strengths:
  • Erythromycin Tablets: 250mg
• Dosing:
  • 250mg taken orally every 6 hours
  • OR 500mg taken orally every 12 hours (if the daily dose does not exceed 1g) 
• Depending on the infection's severity, your doctor may increase the dose up to 4g per day:
  • No dose adjustment for renal impairment
  • Use caution in patients with hepatic impairment
• Paediatric Dosing:
  • Erythromycin Tablets: 250mg
• Dosing:
  • For mild-to-moderate infections: 30-50mg/kg/day taken orally, divided every 6-8 hours
  • For severe infections: 60-100mg/kg/day taken orally, divided every 6-8 hours

Conclusion

Erythromycin stands as a powerful tool in the medical arsenal, offering effective treatment for various bacterial infections. Its versatility, however, comes with the responsibility of proper usage & awareness of the side effects. By adhering to prescribed dosages and understanding its interactions with other medications, patients can maximise erythromycin's benefits while minimising risks. As antibiotic resistance continues to pose global health challenges, the judicious use of erythromycin becomes increasingly crucial. 

FAQs

1. What is erythromycin commonly used for?

Erythromycin is a versatile antibiotic used to treat many bacterial infections. Its primary uses include:

• Respiratory tract infections
• Pertussis (Whooping cough)
• Skin and soft tissue infections
• Intestinal amebiasis
• Pelvic inflammatory disease (PID)
• Syphilis

2. Which is better, erythromycin or amoxicillin?

When taken appropriately, amoxicillin and erythromycin are equally efficacious, but their suitability depends on the specific infection and patient factors. Amoxicillin, a penicillin-type antibiotic, is commonly used for respiratory, ear, and urinary tract infections. On the other hand, erythromycin, a macrolide antibiotic, is often used as an alternative for patients allergic to penicillin and is effective against similar bacterial strains. However, it has a higher possibility of gastrointestinal side effects and drug interactions. The "better" option depends on the infection, the patient's medical history, and potential allergies. The risk of gastrointestinal side effects is significantly lower with amoxycillin than with erythromycin.

3. Who cannot take erythromycin?

Erythromycin is contraindicated (should not be taken) in certain individuals:

• Patients with a known hypersensitivity or allergy to erythromycin or any other macrolide antibiotics 
• Patients who have experienced severe rashes or similar symptoms with erythromycin in the past.
• Patients with a history of cholestatic jaundice
• Patients with a prolonged QT interval
• Patients taking terfenadine, astemizole, or cisapride, as these combinations can lead to serious or life-threatening reactions.

4. Can I use erythromycin every day?

Erythromycin is not recommended for long-term or repeated use, as it may lead to the development of resistant bacteria. It would be best to use it as your doctor prescribes and for the duration specified in the treatment plan.