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Valtrex

Valtrex

About the medicine

How to use Valtrex

Leaflet accompanying the packaging: information for the user

Valtrex, 500 mg, film-coated tablets

valaciclovir (valaciclovirum)

Read the leaflet carefully before taking the medicine, as it contains important information for the patient.

  • Keep this leaflet, you may need to read it again.
  • If you have any further questions, ask your doctor or pharmacist.
  • This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their symptoms are the same as yours.
  • If you experience any side effects, including any not listed in this leaflet, tell your doctor or pharmacist. See section 4.

Table of contents of the leaflet:

  • 1. What is Valtrex and what is it used for
  • 2. Important information before taking Valtrex
  • 3. How to take Valtrex
  • 4. Possible side effects
  • 5. How to store Valtrex
  • 6. Contents of the pack and other information

1. What is Valtrex and what is it used for

Valtrex belongs to a group of medicines called antivirals. It works by killing or slowing the growth of herpes simplex virus (HSV), varicella-zoster virus (VZV), and cytomegalovirus (CMV).
Valtrex can be used to treat:
shingles (in adults);
skin and genital herpes infections (in adults and adolescents over 12 years of age); it is also used to prevent recurrence of these infections;
cold sores (in adults and adolescents over 12 years of age);
prevention of cytomegalovirus (CMV) infections after organ transplantation (in adults and adolescents over 12 years of age);
treatment and prevention of herpes simplex virus (HSV) infections of the eye, which can recur (in adults and adolescents over 12 years of age).

2. Important information before taking Valtrex

When not to take Valtrex

  • If you are allergic to valaciclovir or aciclovir or any of the other ingredients of this medicine (listed in section 6).
  • If you have ever had a widespread rash, fever, enlarged lymph nodes, increased liver enzymes, and/or eosinophilia (drug reaction with eosinophilia and systemic symptoms) after taking valaciclovir. You should not take Valtrex if you have had any of these symptoms. If in doubt, consult your doctor or pharmacist before taking Valtrex.

Warnings and precautions

Before taking Valtrex, tell your doctor or pharmacist if you:

  • have kidney problems
  • have liver problems
  • are over 65 years old
  • have a weakened immune system

If you are unsure whether any of the above apply to you, consult your doctor or pharmacist before taking Valtrex.

Be especially careful when taking Valtrex - important information:

During treatment with valaciclovir, drug reactions with eosinophilia and systemic symptoms (DRESS) have been reported.
In the initial phase of DRESS, flu-like symptoms and facial rash occur, followed by a widespread rash with high fever, elevated liver enzymes, and an increase in white blood cells (eosinophilia) and swollen lymph nodes.

If you experience a rash with fever and swollen lymph nodes, stop taking valaciclovir and contact your doctor or seek medical attention.

Preventing the transmission of genital herpes

If you are taking Valtrex to prevent genital herpes or have had genital herpes in the past, you should continue to practice safe sex, including the use of condoms. This is important to prevent transmission to others. You should avoid sexual contact if you have genital ulcers or blisters.

If you have genital ulcers or blisters, you should avoid sexual contact.
until they have healed.

Valtrex and other medicines

Tell your doctor or pharmacist about all the medicines you have taken recently or plan to take.
If you are taking any medicines that affect the kidneys, tell your doctor or pharmacist. This includes medicines such as aminoglycosides, platinum-based compounds, iodinated contrast agents, methotrexate, pentamidine, foscarnet, cyclosporin, tacrolimus, cimetidine, and probenecid.
If you are taking Valtrex for shingles or after organ transplantation, always tell your doctor or pharmacist.

Pregnancy and breastfeeding

Valtrex is not usually recommended during pregnancy. If you are pregnant or breastfeeding, think you may be pregnant, or plan to have a baby, ask your doctor for advice before taking this medicine. Your doctor will assess whether the benefits to you of taking Valtrex during pregnancy or breastfeeding outweigh the risks to your baby.

Driving and using machines

Valtrex may cause side effects that affect your ability to drive or use machines.
Do not drive or use machines unless you are sure you feel well.

3. How to take Valtrex

Always take this medicine exactly as your doctor has told you.
If you are unsure, ask your doctor.
The dose of Valtrex will depend on why your doctor has prescribed it for you. Your doctor will discuss this with you.

Treatment of shingles

  • The usual dose is 1000 mg (one 1000 mg tablet or two 500 mg tablets) three times a day.
  • Take Valtrex for 7 days.

Treatment of cold sores

  • The usual dose is 2000 mg (two 1000 mg tablets or four 500 mg tablets) twice a day.
  • Take the second dose 12 hours (but not less than 6 hours) after the first dose.
  • Take Valtrex for one day only (two doses).

Treatment of skin and genital herpes infections

  • The usual dose is 500 mg (one 500 mg tablet or two 250 mg tablets) twice a day.
  • For the first infection, take Valtrex for 5 days or up to 10 days if your doctor tells you to. For recurrent infections, the treatment duration is usually 3-5 days.

Prevention of recurrent genital herpes

  • The usual dose is one 500 mg tablet once a day.
  • Some patients with very frequent recurrences may benefit from taking one 250 mg tablet twice a day.
  • Take Valtrex until your doctor tells you to stop.

Prevention of cytomegalovirus (CMV) infection

  • The usual dose is 2000 mg (two 1000 mg tablets or four 500 mg tablets) four times a day.
  • Take doses every 6 hours.
  • Start taking Valtrex as soon as possible after the transplant.
  • Take Valtrex for about 90 days after the transplant, or until your doctor tells you to stop.

Your doctor may adjust the dose of Valtrex if:

  • you are over 65 years old
  • you have a weakened immune system
  • you have kidney problems If any of these apply to you, tell your doctor before taking Valtrex.

Taking the medicine

  • Take the medicine by mouth.
  • Swallow the tablets whole with water.
  • Take Valtrex at the same time every day.
  • Take Valtrex as directed by your doctor or pharmacist.

Patients over 65 years old or with kidney problems

It is very important to drink water regularlywhile taking Valtrex to reduce the risk of kidney problems or nervous system problems. Your doctor will monitor you closely for these symptoms.
Symptoms of nervous system problems may include confusion, agitation, unusual sleepiness, or lethargy.

Taking more Valtrex than prescribed

Valtrex is not usually harmful, unless you take more than the prescribed dose for several days. If you take too many tablets, you may experience nausea, vomiting, kidney problems, confusion, agitation, disorientation, hallucinations, or loss of consciousness. If you have taken too many tablets, contact your doctor or pharmacist. Take the packaging with you.

Missing a dose of Valtrex

  • If you forget to take a dose, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose.
  • Do not take a double dose to make up for a missed dose.

4. Possible side effects

Like all medicines, Valtrex can cause side effects, although not everybody gets them.

Symptoms to look out for:

Stop taking Valtrex and contact your doctor immediately if you experience any of the following symptoms:

Severe allergic reactions (anaphylaxis).These occur rarely in people taking Valtrex.
Sudden symptoms include:

  • redness, itching rash
  • swelling (angioedema) of the face, lips, tongue, or throat, causing difficulty breathing
  • low blood pressure leading to fainting.

Skin rash or redness.Unwanted skin reactions can occur as a rash with or without blisters. There may be skin irritation, swelling (DRESS syndrome), and fever and flu-like symptoms.

Other side effects that may occur:

Very common side effects(may affect more than 1 in 10 people):

  • headache Common side effects:(may affect up to 1 in 10 people):
  • nausea (feeling sick)
  • dizziness
  • vomiting
  • diarrhea
  • skin reaction to sunlight (photosensitivity)
  • rash
  • itching (pruritus)

Uncommon side effects(may affect up to 1 in 100 people):

  • confusion
  • seeing or hearing things that are not there (hallucinations)
  • feeling extremely sleepy
  • shakiness
  • feeling agitated

These nervous system side effects usually occur in people with kidney disease, the elderly, or patients who have had organ transplants and are taking high doses of Valtrex, 8 g or more per day. They usually go away after stopping Valtrex or reducing the dose.
Other uncommon side effects

  • shortness of breath or difficulty breathing (dyspnea)
  • abdominal discomfort
  • rash (sometimes itchy), hives
  • back pain (kidney pain)
  • blood in the urine (hematuria)

Uncommon side effects that may be seen in blood tests:

  • low white blood cell count (leukopenia)
  • low platelet count (thrombocytopenia)
  • increased levels of certain substances (enzymes) produced by the liver. Rare side effects(may affect up to 1 in 1000 people):
  • loss of coordination or balance (ataxia)
  • slow or disturbed speech
  • seizures (convulsions)
  • brain problems (encephalopathy)
  • loss of consciousness (coma)
  • disorientation or confusion

These nervous system side effects usually occur in people with kidney disease, the elderly, or patients who have had organ transplants and are taking high doses of Valtrex, 8 g or more per day. They usually go away after stopping Valtrex or reducing the dose.
Other rare side effects

  • kidney problems, where you do not urinate or urinate very little.

Frequency not known(cannot be estimated from the available data)

  • Drug reaction with eosinophilia and systemic symptoms (DRESS), also known as hypersensitivity syndrome, characterized by widespread rash, high fever, elevated liver enzymes, blood abnormalities (eosinophilia), swollen lymph nodes, and possible involvement of other organs. See also section 2.
  • Kidney inflammation (interstitial nephritis)

Reporting side effects

If you experience any side effects, including any not listed in this leaflet, tell your doctor or pharmacist. You can also report side effects directly to the national reporting system via the Medicines and Healthcare products Regulatory Agency (MHRA) Yellow Card Scheme (www.mhra.gov.uk/yellowcard). By reporting side effects, you can help provide more information on the safety of this medicine.

5. How to store Valtrex

  • Keep the medicine out of the sight and reach of children.
  • Do not use this medicine after the expiry date stated on the packaging. The expiry date (EXP) is the last day of the month stated.
  • Store below 30°C.
  • Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. This will help protect the environment.

6. Contents of the pack and other information

What Valtrex contains

The active substance is valaciclovir. Each film-coated tablet contains 500 mg of valaciclovir (as valaciclovir hydrochloride).
The other ingredients are:
Core:
microcrystalline cellulose
crosprovidone
povidone
magnesium stearate
silica, colloidal anhydrous
Coating:
hypromellose
titanium dioxide (E 171)
macrogol 400
polysorbate 80
carnauba wax

What Valtrex looks like and contents of the pack

Valtrex tablets are packaged in PVC/Al blisters.
Valtrex 500 mg film-coated tablets are available in cartons containing 10, 30, 42, or 112 tablets. The tablets are white, with "GX CF1" engraved on one side.

Marketing authorisation holder and manufacturer

Marketing authorisation holder: Manufacturer:

  • 1. Glaxo Wellcome SA GlaxoSmithKline (Ireland) Limited 12 Riverwalk Citywest Business Campus Dublin 24 Ireland Avenida de Extremadura 3 09400 Aranda de Duero Burgos Spain
  • 2. Delpharm Poznań Spółka Akcyjna ul. Grunwaldzka 189 60-322 Poznań Poland

This medicine is authorised in the Member States of the European Economic Area under the following names:

Austria, Bulgaria, Cyprus, Czech Republic, Estonia, Finland, Greece, Spain, Ireland, Iceland, Lithuania, Latvia, Germany, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Sweden: Valtrex
Belgium, France, Netherlands, Luxembourg, Italy: Zelitrex

Date of last revision of the leaflet: December 2022

  • Country of registration
  • Active substance
  • Prescription required
    Yes
  • Manufacturer
  • Importer
    Glaxo Wellcome S.A. GlaxoSmithKline Pharmaceuticals S.A.

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