erythromycin stearate

Action and Spectrum

Actions and Spectrum: 

erythromycin stearate is a macrolide antibiotic that works by inhibiting bacterial protein synthesis. It binds to the 50S subunit of the bacterial ribosome, preventing the addition of new amino acids to the growing peptide chain, thereby blocking bacterial protein synthesis. 

erythromycin stearate is active against a wide range of gram-positive and some gram-negative bacteria, as well as some atypical bacteria like Mycoplasma pneumoniae, Chlamydia trachomatis, and Legionella pneumophila. It is also effective against some anaerobic bacteria, but not all. 

The spectrum of activity of erythromycin stearate includes: 

• Streptococcus pneumoniae 
• Streptococcus pyogenes (group A streptococci) 
• Staphylococcus aureus (but not methicillin-resistant strains) 
• Haemophilus influenzae 
• Mycoplasma pneumoniae 
• Chlamydia trachomatis 
• Legionella pneumophila 
• Bordetella pertussis 
• Corynebacterium diphtheriae 
• Neisseria gonorrhoeae 

erythromycin stearate is commonly used to treat respiratory tract infections, skin and soft tissue infections, and sexually transmitted infections. However, the emergence of erythromycin-resistant bacteria has limited its usefulness in some cases. 

Drug Interaction

Adverse Reaction

Frequency defined 

1-10% 

Hypertrophic pyloric stenosis 

Rash (3%) 

Tinnitus 

Abdominal pain (8%) 

Vomiting (3%) 

Skin eruptions 

Dyspepsia (2%) 

Nausea (8%) 

Pseudomembranous colitis 

Flatulence (2%) 

Anaphylaxis 

Pruritus (1%) 

Mild allergic reactions 

Headache (8%) 

Urticaria 

Fever 

Diarrhea (7%) 

Pain (2%) 

<1% 

Confusion 

Hallucinations 

Hearing loss 

Torsade de pointes 

Hypotension 

Cholestatic hepatitis 

Ventricular tachycardia 

Vertigo 

Frequency not defined 

Interstitial nephritis 

Black Box Warning

Black Box Warning: 

erythromycin stearate has a black box warning for an increased risk of cardiac arrhythmias, mainly when used concomitantly with certain other medications, such as antiarrhythmic agents and drugs that prolong the QT interval. 

erythromycin stearate can also cause hepatotoxicity (liver damage), especially in high doses or prolonged use. Patients with pre-existing liver disease or taking other hepatotoxic drugs may be at increased risk of developing liver toxicity. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication 

erythromycin stearate is contraindicated in individuals with hypersensitivity to erythromycin or other macrolide antibiotics. 

Additionally, erythromycin stearate should not be used in patients with: 

• Prolonged QT interval or a history of ventricular arrhythmias 
• Liver disease, including hepatic impairment, hepatitis, and cirrhosis 
• Myasthenia gravis, a neuromuscular disorder that causes muscle weakness and fatigue 
• Porphyria, a group of rare genetic disorders conditions that affect the production of heme, a component of hemoglobin. 

erythromycin stearate should also be used cautiously in patients with a history of gastrointestinal disease or who are currently taking medications that may interact with erythromycin. Specific antiarrhythmic agents and some drugs prolong the QT interval. 

It is essential to discuss any medical conditions or medications with a healthcare provider before taking erythromycin stearate. 

Caution 

• Drug Interactions: erythromycin stearate may interact with other medications, including some antiarrhythmic agents, some drugs that prolong the QT interval, and certain statins. It would be best to inform your healthcare provider of all medications before starting erythromycin stearate. 
• Gastrointestinal Issues: erythromycin stearate may cause gastrointestinal disturbances such as nausea, vomiting, diarrhea, and abdominal pain. Patients with a history of gastrointestinal disease should use erythromycin stearate with caution. 
• Liver Function: erythromycin stearate can cause hepatotoxicity (liver damage), especially in high doses or prolonged use. Patients with pre-existing liver disease or taking other hepatotoxic drugs should use erythromycin stearate with caution. 
• QT Prolongation: erythromycin stearate can prolong the QT interval, leading to serious cardiac arrhythmias. Patients with a history of cardiac arrhythmias or other heart conditions should use erythromycin stearate cautiously. 
• Allergic Reactions: Rarely, erythromycin stearate can cause severe allergic reactions, including anaphylaxis. Patients with prior history of allergic reactions should use erythromycin stearate cautiously. 
• Pregnancy and Breastfeeding: erythromycin stearate should be used cautiously in pregnant or breastfeeding women, as it may cross the placenta or be excreted in breast milk. 

Pregnancy / Lactation

Pregnancy consideration:  

AU TGA pregnancy category: A
US FDA pregnancy category: Not assigned 

Lactation:   

Excreted into human milk: Yes. 

Pregnancy category: 

• Category A: well-controlled and Satisfactory studies do not show risk to the fetus in the first/later trimester.        
• Category B: there was no evidence of risk to the fetus in animal studies, and there were not enough studies on pregnant women        
• Category C: there was evidence of risk of adverse effects in animal reproduction studies, and no adequate evidence in human studies must take care of potential risks in pregnant women.       
• Category D: adequate data with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits.        
• Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women.        
• Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology: 

erythromycin stearate is a macrolide antibiotic that works by inhibiting bacterial protein synthesis. Specifically, it binds to the 50S ribosomal subunit of the bacterial ribosome, preventing the formation of peptide bonds between amino acids and thus inhibiting the translation of bacterial proteins. This ultimately leads to the inhibition of bacterial growth and reproduction. 

erythromycin stearate has broad-spectrum activity against a range of gram-positive and gram-negative bacteria and some atypical bacteria. It is particularly effective against Streptococcus, Staphylococcus, Haemophilus influenzae, Legionella pneumophila, and Mycoplasma pneumoniae. 

Pharmacodynamics: 

Mechanism of action: The drug’s action hinders bacterial growth, likely by impeding the separation of peptidyl transfer RNA from ribosomes. This causes a cessation of RNA-dependent protein synthesis. 

Pharmacokinetics: 

Absorption 

erythromycin stearate is well-absorbed in the gastrointestinal tract after oral administration. The absorption is enhanced when erythromycin stearate is taken with food. Peak plasma concentrations are reached within 1-2 hours of oral administration. 

Distribution 

erythromycin stearate is widely distributed in body tissues, including the lungs, liver, spleen, and kidneys. It can also cross the placenta and enter breast milk. erythromycin stearate is approximately 70% protein-bound in plasma. 

Metabolism 

erythromycin stearate is metabolized primarily in the liver by the cytochrome P450 enzyme system. The major metabolite of erythromycin stearate is desmethyl erythromycin, which has antibiotic activity but is less potent than the parent compound. Other minor metabolites include erythromycin estolate, which has been associated with hepatotoxicity. 

Elimination and Excretion 

erythromycin stearate and its metabolites are primarily excreted in the bile, with a small fraction excreted in the urine. The elimination half-life of erythromycin stearate is approximately 1.5 hours in healthy adults, but it can be prolonged in patients with impaired liver function. 

Adminstartion

Administration: 

Oral administration 

erythromycin stearate is available in various forms, including tablets, capsules, and oral suspension. The administration of erythromycin stearate may vary depending on the form of the medication and the condition being treated. Here are some general guidelines for the administration of erythromycin stearate: 

• Follow your healthcare provider’s directions or the instructions on the medication label carefully. 
• erythromycin stearate is usually taken by mouth, with or without food. Taking erythromycin stearate with food may help reduce gastrointestinal side effects. 
• If you take the tablet or capsule form of erythromycin stearate, swallow it whole with a full glass of water. Do not crush/chew the tablet or capsule. 
• If you are taking the oral suspension form of erythromycin stearate, use a measuring device to ensure accurate dosing. Shake the suspension well before each use. 
• Take erythromycin stearate at evenly spaced intervals to maintain a constant level of the drug in your system. 
• Do not stop taking erythromycin stearate without consulting your healthcare provider, even if you start to feel better. Completing the entire course of treatment is vital to ensure the infection is fully treated and prevent antibiotic resistance development. 
• If a dose is missed, it is recommended to take it as soon as possible. However, if the next scheduled dose is missed, it should be skipped and the following dose should be taken at the appropriate time. It is important to avoid taking a double dose of the medication to compensate for the missed dose. 
• Store erythromycin stearate at room temperature, away from heat and moisture, and keep it out of reach of children. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: erythromycin stearate 

Pronounced: [ er-ITH-roe-MYE-sin ] 

Why do we use erythromycin stearate? 

erythromycin stearate is a type of macrolide antibiotic that is used to treat a variety of bacterial infections. Here are some of the common uses of erythromycin stearate: 

• Respiratory Infections: erythromycin stearate treats respiratory tract infections, including pneumonia, bronchitis, and pertussis (whooping cough). 
• Skin Infections: erythromycin stearate treats skin infections like cellulitis and impetigo. 
• Genital and Urinary Tract Infections: erythromycin stearate is used to treat infections of the genital and urinary tracts, including chlamydia and gonorrhea. 
• Gastrointestinal Infections: erythromycin stearate treats gastrointestinal infections, such as bacterial gastroenteritis and Helicobacter pylori infection. 
• Rheumatic Fever: erythromycin stearate is used to prevent and treat rheumatic fever, a complication of streptococcal infections. 
• Preoperative Prophylaxis: erythromycin stearate may be used as a prophylactic (preventive) measure before surgery to prevent bacterial infection. 

erythromycin stearate may also be used for other conditions a healthcare provider determines. It is crucial to use erythromycin stearate only for the condition it is prescribed for and to complete the entire course of treatment to ensure the infection is treated and to prevent the development of antibiotic resistance.