Erythromycin Oral Dose and Uses
Erythromycin guidance for selected bacterial infections including pertussis, pneumonia, diphtheria, and chlamydial infections.
Also searched as
Source reviewed
source date listed on the source page
Guide category
Oral drugs
Safety boundary
Prescription medicine information for clinician-guided use.
Kenza Health Hub presents this medicine page as structured health education. Check dose, route, interactions, pregnancy or breast-feeding considerations, and local protocol with a qualified clinician or pharmacist. Read our medical editorial policy.
Quick clinical summary
| Item | Summary |
|---|---|
| Drug | Erythromycin |
| Class | Macrolide antibacterial |
| Common forms | 250 mg tablet or capsule; 125 mg/5 ml suspension |
| Key uses | Selected bacterial infections including pertussis, diphtheria, atypical pneumonia, and chlamydial infections |
| Dose rhythm | Usually four times daily in the source guidance |
| Major cautions | QT prolongation, gastrointestinal effects, hearing effects, and interactions |
| Monitoring | Clinical response, tolerability, and interacting QT-prolonging medicines |
Clinical context from Kenza
The sections below add practical explanation around the source-derived monograph. They are educational context and do not replace local protocols or clinician review.
Why erythromycin is interaction-heavy
Erythromycin belongs to the macrolide class. This class can interact with several medicines and may add to QT prolongation risk, so a current medication list is important before treatment.
Four-times-daily dosing and adherence
The source dose schedule requires repeated daily doses. Missing doses or stopping early can reduce treatment success, while taking extra doses can increase adverse effects.
When alternatives may be considered
Related macrolides and penicillins may appear in nearby treatment pathways. Choice depends on the infection, allergy history, pregnancy or breast-feeding status, resistance patterns, and local protocol.
Therapeutic action
Macrolide antibacterial.
Indications
- Pertussis, diphtheria, atypical pneumonia, cervicitis and urethritis due to Chlamydia trachomatis, and other erythromycin-susceptible infections.
Forms and strengths
- 250 mg tablet or capsule.
- 125 mg/5 ml oral suspension.
Dose
- Child: 10 to 12.5 mg/kg 4 times daily.
- Adult: 500 mg 4 times daily.
| Age | Weight | Daily dose | 125 mg/5 ml susp. | 250 mg tablet | 500 mg tablet |
|---|---|---|---|---|---|
| 1 to < 2 months | 4 to < 5 kg | 62.5 mg x 2 | 2.5 ml x 2 | ¼ tab x 2 | − |
| 2 to < 12 months | 5 to < 10 kg | 125 mg x 2 | 5 ml x 2 | ½ tab x 2 | ¼ tab x 2 |
| 1 to < 3 years | 10 to < 15 kg | 250 mg x 2 | 10 ml x 2 | 1 tab x 2 | ½ tab x 2 |
| 3 to < 8 years | 15 to < 25 kg | 250 mg x 3 | 10 ml x 3 | 1 tab x 3 | ½ tab x 3 |
| 8 to < 11 years | 25 to < 35 kg | 500 mg x 2 | − | 2 tab x 2 | 1 tab x 2 |
| 11 to < 13 years | 35 to < 45 kg | 500 mg x 3 | − | 2 tab x 3 | 1 tab x 3 |
Duration
According to indication and clinical response.
Contra-indications, adverse effects, precautions
- Do not administer to patients with allergy to erythromycin or another macrolide.
- May cause gastrointestinal disturbances, reversible hearing disorders, and QT prolongation.
- Avoid or monitor combinations with drugs that prolong the QT interval and with medicines whose concentrations are increased by macrolides.
- Pregnancy and breast-feeding: no contra-indication.
Frequently Asked Questions
Erythromycin oral dose and administration questions
What is erythromycin oral used for?
This guide lists erythromycin for pertussis, diphtheria, atypical pneumonia, cervicitis and urethritis due to Chlamydia trachomatis, and other susceptible infections.
What strengths of erythromycin oral are listed?
The listed forms are 250 mg tablet or capsule and 125 mg/5 ml oral suspension.
What is the erythromycin oral dose?
The listed dose is 10 to 12.5 mg/kg 4 times daily in children and 500 mg 4 times daily in adults.
What precautions matter with erythromycin?
The page notes allergy to erythromycin or another macrolide, gastrointestinal effects, reversible hearing disorders, QT prolongation, and the need to avoid or monitor combinations with QT-prolonging drugs.
Source
MSF Essential drugs practical guidelines (January 2026)
This page combines source-derived medicine reference sections with Kenza editorial context, while leaving out the Storage and Remarks sections from the source batch.
Additional medical references
Rate this guide
Be the first to rate this guide.