Used for: Herpes zoster (Shingles), Herpes simplex virus infections, Cold sores, Varicella-zoster virus infections
Chinese name:

What is Zovirax?

Zovirax is a brand medication that contains Acyclovir, which belongs to a class of antivirals. It works by inhibiting the DNA synthesis of viruses to destroy viruses. It is therefore used to treat viral infections like herpes simplex virus types 1 and 2, varicella-zoster virus (herpes zoster and chickenpox), cold sores, Herpes zoster virus infections (Shingles).

How to use it?

Zovirax is available as cream, tablets, oral suspension and IV infusions. 

For recurrent herpes simplex virus infections,
Take 800mg daily in 2-4 divided doses and may reduce it to 400-600mg daily. Conditions should be reassessed every 6-12 months


For mild or infrequent recurrences,

200mg 5 times daily for 5 days, preferably begin during the prodromal period


For primary herpes simplex infections, 
Adult / Child above 2 years 
Take 200mg 5 times daily, usually every 4 hours while awake for 5-10 days. 

For severely immunocompromised patients: 400mg 5 times daily for 5 days

For Herpes Zoster (Shingles),
Take 800mg 5 times daily for 7-10 days

For Varicella-Zoster virus infections,
Take 800mg 4 or 5 times a daily for 5-7 days

Children above 2 years
20 mg/kg (up to a maximum of 800 mg), 4 times daily for 5 days

For Cold sores, 
Apply 5 or 6 times daily for 5-10 days, preferably apply in the prodromal period (Tingling sensation on the lips)

What are the side effects of Zovirax?

Common side effects of Zovirax include stomach discomfort, diarrhoea, dizziness, headache, nausea, sensitivity to sunlight (photosensitivity), skin reactions, and vomiting.

Who should not take Zovirax?

  • Anyone who has an allergy to Zovirax or any other components of the product.

Pharmacist Tips:

  • Wash your hands before and after applying Acyclovir cream.
  • Complete the whole course to ensure the viral infection is cleared up.

Common dosing schedule: 

Zovirax may be taken with or without food.


This schedule is for reference only, adjustments may be made according to individual needs.


Some common medications Zovirax may interact with:

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Zovirax in Hong Kong?

In Hong Kong, Zovirax 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 https://www.drugoffice.gov.hk

Need more information?

For detailed information about the use of Zovirax 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.

Available dosage
  • 5% (Cream)
  • 250mg (Infusions)
  • 200mg/5ml (Oral Suspension)
  • 200mg / 400mg / 800mg (Tablets)
Drug class
Sub class
Viral DNA Polymerase Inhibitors
Generic Names
Other drugs in same class
Used for: Herpes simplex virus infections, Varicella-zoster virus infections
Chinese name: