Valaciclovir - oral

Patient Medicine Information
Why do I need this medicine?
Valaciclovir is a medicine used to treat viral infections.

This medicine is used to treat herpes infections such as herpes zoster (shingles) or shingles affecting the eyes. It may also be used to treat cold sores or infections of the skin or genitals that is caused by the herpes simplex virus.

This medicine may also be used after an organ transplant to prevent an infection with a virus called cytomegalovirus (CMV).

Valaciclovir may also be used to treat other conditions as decided by your doctor.
How do I take this medicine?
Take this medicine exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

You may take Valaciclovir with or without food. Try to take it at the same time each day.

If you experience any stomach discomfort, you may take this medicine with food.

The dose of this medicine will be decided by your doctor. Your doctor will advise you on the treatment timeframe depending on the type and severity of your infection.

Valaciclovir must be taken at regular intervals for it to be effective. Continue taking this medicine even when you feel better. Do not stop taking it unless instructed by the doctor.

Do not skip any doses. You must complete the entire course of medicine. If you don't, the infection will not be properly controlled.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.

If you often forget to take your medicine, let your doctor and pharmacist know.
When should I not use this medicine?
Alert your doctor if you ever had an allergic reaction (rashes, breathlessness, swollen eyes) to Valaciclovir or any similar antiviral medications such as aciclovir.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:
  • kidney disease
  • liver disease
  • weak immune system
  • inadequately hydrated or at risk of dehydration
Let your doctor know if you are pregnant or breastfeeding.

Be sure to check with your doctor or pharmacist before giving this medicine to an elderly. Elderly may be more sensitive to the side effects.

Valaciclovir does not reduce your risk of passing genital herpes to other people through sexual contact. Ensure that you take proper precautions to avoid spreading herpes virus infection to others. Practice safe sex and use condoms to protect your partner. If you still have genital sores or blisters, you should avoid sexual contact until the doctor certifies that you are cleared of the infection.

Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly. You may need to have routine blood tests (e.g. complete blood count, liver and kidney function) to check your body’s response to the medicine. Your doctor will advise you how often you need to have these tests.
What side effects could I experience?
Valaciclovir may cause any of the following side effects: headache, nausea, vomiting, stomach pain, diarrhoea, dizziness, tiredness, and increased sensitivity of the skin to sunlight.

Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
  • rashes, breathlessness, swelling of the face, eyes, mouth or throat
  • fever with persistent sore throat or mouth ulcers, unusual bleeding or bruising
  • unusual changes in mood and behaviour (being too depressed or agitated)
  • confusion and hallucinations (seeing, hearing or feeling things that are not existent)
  • signs of kidney problems e.g. blood in urine, difficulty passing urine
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking any of these medicines:
  • other medicines for viral infections e.g. tenofovir, foscarnet
  • cimetidine (medicine that reduce stomach acid production)
  • probenecid (medicine for gout)
  • methotrexate (medicine for cancer)
  • medicines used in organ transplant or certain immune disorders e.g. ciclosporin, tacrolimus
This list does not include all medicines that may interact with Valaciclovir.

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on valaciclovir - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2024 MIMS. All rights reserved. Powered by
  • Norus
  • Valvir
  • Vandavir
  • Zostavir
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Already a member? Sign in
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Already a member? Sign in