Medicines & Supplements A to Z > Erythromycin


Last updated on July 12, 2019.

Overview   |   Dosage   |   Side Effects   |   Where To Buy  


GENERIC NAME: Erythromycin


COMMON BRANDS IN HONG KONG: Elosone, Erotab, Irosin, Aknemycin, Erylik 伊暗瘡膏 (contains Erythromycin and Tretinoin)

What is Erythromycin for?

Erythromycin is a macrolide antibiotic like Azithromycin, and is used for treating bacterial infections, including but not limited to the following: 

  • Acute otitis media (ear infection) 
  • Respiratory tract infections 
  • Pertussis (Whooping cough)
  • Skin and soft tissue infections 
  • Acne 
  • Other susceptible infections 

How to use it?

Erythromycin can be taken by mouth or applied to the skin. It should be taken on an empty stomach (about 2 hours after a meal). The dosages for different uses and age groups are listed below: 

For acute otitis media (ear infection) 

By mouth 

Child 1-23 months 

125 mg 4 times daily for 5-7 days OR 250 mg twice daily for 5-7 days. 

Child 2-7 years 

250 mg 4 times daily for 5-7 days OR 500 mg twice daily for 5-7 days. 

Child 8-17 years

250-500 mg 4 times daily for 5-7 days OR 500-1000 mg twice daily for 5-7 days. 

For acne (in adults)

By mouth 

Start with 250 mg daily and may increase up to 500 mg twice daily. 

To the skin using 2-4% solution / gel / ointment 

Apply to the affected areas 1-2 times daily for a maximum duration of 6 months. If your conditions worsen or show no improvement after 6-8 weeks of use, you should tell your doctor and discontinue the treatment. 

For respiratory tract infections / skin and soft tissue infections / other susceptible infections 


1-2 g daily in 2-4 divided doses and may increase up to 4 g daily in severe cases. You should take the dose that is above 1 g in more than 2 divided doses. 


30-50 mg/kg daily in 2-4 divided doses and may double the dose in severe cases.

What are the side effects of Erythromycin?

Common side effects of Erythromycin include decreased appetite, diarrhoea, gastrointestinal discomfort, nausea, and vomiting.

Where to buy Erythromycin in Hong Kong?

In Hong Kong, Erythromycin is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

For detailed information about the use of Erythromycin in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.