Consumer medicine information

ZOVIRAX® 800 mg Tablets (120 tablet pack)


Consumer Medicine Information

What is in this leaflet

The information provided in this leaflet applies to usage of the 120 tablet packs.

This leaflet answers some common questions about Zovirax. It does not contain all of the available information.

Reading this leaflet does not take the place of talking to your doctor or pharmacist.

Taking any medicine involves some risk. It is possible that all risks associated with this medicine might not have been detected, despite proper testing. Only your doctor or pharmacist is able to weigh up all of the relevant facts, and you should consult them if you have any queries.

If you have any concerns about taking Zovirax ask your doctor or pharmacist.

Keep this information. You may want to read it again.

This leaflet provides information about Zovirax.

The statements that are made in this leaflet cannot be applied to any other medicine, even those that are similar or appear to contain the same ingredients.

What Zovirax is used for

Zovirax is used as part of the management program for certain infections in people who also have the human immunodeficiency virus (HIV). HIV is the virus that causes acquired immune deficiency syndrome (AIDS).

Zovirax does not cure AIDS or get rid of the HIV virus from your body, but it may prevent further damage to the immune system by stopping production of herpes viruses.

How does Zovirax work?

Aciclovir (the active ingredient in Zovirax) belongs to a group of medicines called “antivirals”.

Zovirax works by stopping the production of the viruses that cause herpes and shingles.

Your doctor may, however, have prescribed Zovirax for a different use to that described above.

If you have any questions about why you are taking Zovirax ask your doctor or pharmacist. Your doctor or pharmacist will be able to provide you with more information.

Before you take Zovirax

Zovirax is not suitable for everyone.

Be sure that your doctor knows about the following before you take Zovirax:

  1. If you are allergic to:
    – Aciclovir (the active ingredient in Zovirax) or valaciclovir;
    – Any other ingredient listed at the end of this leaflet.
  2. If you are pregnant, or become pregnant while using Zovirax, or are breastfeeding.
  3. If you suffer from:
    – A kidney or liver condition; or
    – A blood condition, or
    – Any condition affecting your brain

Taking other medicines

Tell your doctor or pharmacist if you are taking any other medications, including any that you get without a prescription from your pharmacy, supermarket or health food shop.

Some medicines and ZOVIRAX may interfere with each other. These include:

  • medicines used to prevent gout or gouty arthritis such as probenecid
  • medicines used to treat gastric ulcers or reflux such as cimetidine
  • fluid tablets (diuretics)
  • medicines used prevent rejection of transplanted organs such as mycophenolate mofetil.

These medicines may be affected by ZOVIRAX or may affect how well it works. You may need different amounts of your medicines, or you may need to take different medicines.

Your doctor and pharmacist have more information on medicines to be careful with or avoid while taking this medicine. When you must not take Zovirax.

Do not take Zovirax after the expiry date printed on the pack.

Do not take Zovirax if the packaging shows signs of tampering.

Do not take Zovirax to treat any other conditions unless advised by your doctor.

Do not give Zovirax to anyone else, even if their symptoms seem similar to yours.

Taking Zovirax

Take Zovirax as directed by your doctor or pharmacist. Never change the dosage yourself.

Your doctor and pharmacist will be able to tell you:

  • how many tablets to take as each dose;
  • how many doses to take each day;
  • when to take each dose.

The label on the pack that the tablets were supplied in will give the same information. If there is something that you do not understand, ask either your doctor or pharmacist.

The usual dose of Zovirax in the management of HIV is one tablet four times daily. Your doctor may vary your Zovirax dosage if you also suffer from other medical conditions.

If you have any questions about the dose that you have been prescribed, you should ask your doctor or pharmacist.

How to take Zovirax

Your Zovirax tablets may be swallowed whole with a glass of water, or dispersed in a quarter of a glass of water (about 50 ml) and then swallowed.

If you forget to take your dose

If you have just missed your scheduled dose, take it as soon as you remember and continue as before.

If you have forgotten to take one dose of Zovirax and it is almost time to take your next scheduled dose, then skip the dose you have missed, and continue taking your Zovirax as directed by your doctor or pharmacist.

If you have forgotten to take more than one dose, contact your doctor or pharmacist for advice.

Do not take a double dose to make up for the dose that you have missed.

If you have trouble remembering when to take your medicine, ask your pharmacist for some hints.

In case of overdose

Immediately contact your doctor or Poisons Information Centre (telephone 13 11 26) for advice, or go to accident and emergency at your nearest hospital, if you think that you may have taken too much, or if anyone else may have taken too much Zovirax. Do this even if there are no signs of discomfort or poisoning. You may need urgent medical attention.

Keep telephone numbers for these places handy.

While you are taking Zovirax

Drink plenty of plain fluids.

Your doctor or pharmacist will be able to tell you whether there are any special instructions while you are taking Zovirax.

See your doctor if you feel that your condition is not improving or getting worse.

Driving and using machines

Some side effects such as feeling drowsy or sleepy may impair your ability to concentrate and react. Make sure you are not affected before you drive or operate machinery.

When to stop taking Zovirax

Keep taking Zovirax for as long as your doctor recommends.

Do not stop taking Zovirax just because you feel better. Your doctor will advise you when to stop taking Zovirax.

If you are unsure whether you should stop taking Zovirax, talk to your doctor or pharmacist.

Side effects

All medicines can have some side effects. Sometimes they are serious. Most of the time they are not.

In a few people, Zovirax may have some unwanted side effects.

Make sure that your doctor or pharmacist knows as soon as possible if you do not feel well while you are taking Zovirax. Often it is difficult to tell the difference between side effects of medication and symptoms of the underlying illness.

Tell your doctor if you notice any of the following:

  • Severe allergic reactions (rare). Signs include: itchy, bumpy rash (hives), swelling sometimes of mouth causing difficulties breathing, collapse. Contact your doctor immediately if you get these symptoms. Stop taking Zovirax.
  • Nausea, vomiting, diarrhoea, stomach pain, headache, dizziness, confusion, hallucinations, seizures, fatigue, itching, skin reaction after sunlight exposure, and fever.

Less common side effects include:

  • Liver disorders.
  • Changes in blood test.

A small number of patients have had other unwanted effects after taking Zovirax.

There is no evidence that Zovirax is addictive.

Ask your doctor or pharmacist to answer any questions you may have.

Do not be alarmed by this list of possible side effects. You may not experience any of them.

After taking Zovirax

If your doctor advises you to stop taking Zovirax, ask your pharmacist what to do with any remaining tablets.


Keep your tablets in the pack that they were supplied in.

Keep Zovirax in a cool, dark and dry place where the temperature stays below 30°C.

Do not store Zovirax in the bathroom or near a sink. Heat and dampness may affect Zovirax.

Keep Zovirax, and all other medicines, where children cannot reach them.

Do not leave Zovirax in the car on hot days.

Product description

What Zovirax looks like

Zovirax tablets are white, biconvex, oval, film-coated tablets, branded GXCG1 on one face and plain on the other. They are available in packs of 35 tablets or 120 tablets.

This CMI refers to the 120’s tablet pack.


Zovirax contains 800 mg of the active ingredient aciclovir.

Zovirax also contains:

  • cellulose-microcrystalline
  • povidone
  • sodium starch glycollate
  • aluminium magnesium silicate
  • magnesium stearate
  • macrogol 8000
  • coating opadry Y-1-7000 concentrate


Zovirax tablets are supplied in Australia by:
GlaxoSmithKline Australia Pty Ltd
Level 4, 436 Johnston Street
Abbotsford, Victoria, 3067

This leaflet was prepared on 13 February 2015.

AUST R 51429

The information provided applies only to Zovirax 800 mg tablets.

Zovirax® is a registered trade mark of the GlaxoSmithKline group of companies.

© 2013 GlaxoSmithKline

Version 5.0

Published by MIMS July 2015