Valtrex (Valaciclovir)

Valtrex, also known by its generic name Valaciclovir, is an antiviral medicine used to treat infections caused by certain viruses. The active ingredient in Valtrex is valaciclovir.

It is commonly prescribed for:

• Cold sores and genital herpes (caused by Herpes simplex virus)
• Chickenpox (caused by the varicella-zoster virus)
• Shingles (Herpes Zoster) (caused by the varicella-zoster virus)

It comes in tablet form and is taken orally with or without food. Your doctor will determine the appropriate valaciclovir dosage based on your condition.

After being patented in 1987, Valaciclovir was approved for commercial use in 1995 under the brand name Valtrex. It is listed on the World Health Organisation (WHO) Model List of Essential Medicines.

While Valtrex effectively manages viral infections, it is not a cure. It does not prevent the spread of viruses to others or protect against all viral infections.

Valtrex is a potent antiviral medication that is used to treat several viral infections, including herpes zoster (shingles) and genital herpes. Its effectiveness in managing these conditions is well-documented in clinical settings and supported by a strong foundation of scientific research.

Dr. Caroline Fontana Lead Prescribing Doctor

When ingested, Valtrex (valaciclovir) is converted into aciclovir, its active form.

Aciclovir works by inhibiting the herpes virus’ ability to replicate by blocking a crucial enzyme it needs to reproduce, known as DNA polymerase. This action helps reduce the severity and duration of symptoms such as pain, itching, and blisters, promoting faster healing.

Additionally, Valtrex can be taken daily as a preventative measure to decrease the frequency of outbreaks and reduce the risk of spreading the virus to others.

Valtrex offers several benefits for managing viral infections:

1. Effective treatment of shingles: reduces pain and promotes faster healing.
2. Management of Herpes Simplex: shortens healing time and reduces the severity of cold sores and genital herpes.
3. Suppressive therapy: significantly reduces the frequency of herpes outbreaks when taken as a preventative measure.
4. Convenient form of administration: Valtrex 500 mg tablets are easy to take.
5. Wide range of uses: treats various conditions caused by herpes viruses.
6. Proven efficacy: duration of viral shedding (duplication) was halved in those taking valaciclovir compared to a placebo.

Overall, Valtrex is a reliable and effective antiviral medication that improves the quality of life for individuals with viral infections.

Valtrex is highly effective in treating and managing herpes simplex viral infections.

See the table below for an overview of the effectiveness of valaciclovir for different medical conditions:

Suppression of herpes

One clinical trial found that out of 743 people taking valaciclovir, only 4 developed symptomatic HSV-2 infections (genital herpes). In contrast, 16 out of 741 people taking a placebo developed symptomatic HSV-2.

This means that, when taking Valtrex as a once-daily preventative treatment, you are around 75% less likely to experience an outbreak of genital herpes.

Duration of symptoms

This clinical study found that, in those taking valaciclovir, the average time it took for symptoms of herpes to resolve was 4.8 days.

Comparatively, it took an average of 5.8 days for symptoms to resolve in those taking a placebo.

This means Valtrex reduces the duration of symptoms by 1 day on average.

Who can take it?

You can take Valtrex if your doctor has prescribed it to you. The treatment is prescribed for those over 18 with a herpes virus.

Who cannot take it?

Valtrex may not be suitable for everyone. Avoid taking Valtrex if you:

• Have a known allergy to valaciclovir or aciclovir.
• Have ever developed an extended rash, a fever, or enlarged lymph nodes after taking valaciclovir.

Furthermore, there are some circumstances that will mean Valtrex is prescribed on a case-by-case basis. Inform you doctor if you:

• Have kidney problems
• Have liver problems
• Are over 65 years of age
• Have a weak immune system
• Are pregnant or breastfeeding

Who should be wary of taking Valtrex?

Kidney problems

Over 65 years old

Pregnant or breastfeeding

Weak immune system

Liver problems

You should always swallow tablets whole, with a glass of water. Do not crush, split or break tablets. Whilst taking Valtrex, it’s important you stay hydrated, as this can reduce the risk of renal (kidney) complications and other adverse effects.

If you forget to take Valtrex, take it as soon as you remember. However, if it is nearly time for your next dose, skip your missed dose and continue the course from your next scheduled dose.

Valtrex should always be taken for the full course, regardless of whether the symptoms subside during your treatment.

Dosage & treatment course

The course of treatment will vary depending on which herpes infection you have. Dosage will also vary depending on whether you’re treating an initial bout or a recurrence of the infection, or whether you are just preventing infection.

Here’s a helpful table listing the recommended doses of Valaciclovir:

Note: Valaciclovir is commonly available as 500 mg tablets under the brand name Valtrex. Adjust the number of tablets based on the strength prescribed by your doctor. These dosages are typical, but your dose may differ depending on the severity of your symptoms, kidney and liver health, or age.

When do I take it?

At the first sign of an outbreak: for the best results, take Valtrex as soon as you notice symptoms of any herpes virus.

For preventative treatment: if using Valtrex to prevent outbreaks, take it daily at the time your doctor prescribes.

How do I take it?

Here are some tips on how to take Valtrex from one of our doctors:

• Swallow whole: Swallow the tablet whole with a glass of water.
• With or without food: You can take Valtrex with or without food.
• Follow dosage instructions: Take the exact dose prescribed by your doctor. Do not change your dose without consulting your healthcare provider.
• Stay hydrated: Drink plenty of water throughout the day to stay hydrated, especially if you have kidney problems.
• Consistent timing: Take your medication at the same time daily to help remember and maintain consistent levels in your bloodstream.

What if I miss a dose?

Follow these instructions if you miss a dose of Valtrex:

• If you miss a dose of Valtrex, take it as soon as you remember. 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.

Valtrex begins to work soon after you take your first dose, but the time it takes to see noticeable improvement can vary depending on the condition being treated.

Here’s a simple breakdown:

Remember, these are average timelines. Your body’s response can depend on several factors, including your overall health, the stage of your infection when you start taking the medication, and your adherence to the prescribed Valtrex dosage.

Consult your doctor if you have concerns about how Valtrex is working for you.

As with all prescription medications, you may experience some side effects when taking Valtrex.

These symptoms are rarely a cause for concern and will usually pass quickly. However, if they persist or worsen, contact your doctor.

Less common side effects

Some people may experience side effects of Valtrex that are less common. These can be a sign of something more serious.

Severe conditions (very rare)

• Breakdown of red blood cells (Hemolytic Anaemia)
• Blood clotting issues (Thrombotic Thrombocytopenic Purpura, TTP)

These can lead to serious health issues. If you notice any of these, seek medical attention immediately.

Allergic reactions

If you experience a sudden onset of any of the following symptoms, you may be experiencing an allergic reaction (anaphylaxis):

• skin flushing, itchy skin rash
• swelling of the lips, face, neck and throat which causes difficulty breathing
• sudden drop in blood pressure, leading to collapse

Allergic reactions are rare, but symptoms should not be ignored. If you experience any, stop taking Valtrex and seek immediate medical advice.

Please refer to the patient information leaflet for a complete list of side effects, including rare and serious ones. It will be sent in the box with your medication and can be downloaded from this page.

Yes, Valtrex can interact with some medications. This can affect how either drug works or increase your risk of experiencing side effects.

It is important to inform your doctor about all medications you take, including over-the-counter drugs, vitamins, and herbal supplements.

Here are some medications that may interact with Valtrex and how:

Medications that may increase the potency of Valtrex

• Probenecid (for gout)
• Cimetidine (for heartburn)

Taking these medications may increase the concentration of Valtrex in the blood. This could heighten your risk of experiencing side effects and affect how much you absorb.

Medications affected by Valtrex

• Theophylline (for asthma)
• Zidovudine (for HIV/AIDS)

Valtrex can reduce the effectiveness of these drugs.

Vaccines

• Varicella vaccine
• Zoster vaccine

Valtrex can reduce the effectiveness of these vaccines. Those who have recently had them should wait at least 14 days before using Valtrex.

Other medications

• Other antiviral drugs: taking other antiviral drugs along with Valtrex can increase the risk of side effects, as well as increasing your chance of taking an unsafe dose.
• Immunosuppressants: drugs that suppress the immune system, such as mycophenolate mofetil and ciclosporin, can interact with Valtrex, especially in patients who have had organ transplants.
• Nephrotoxic drugs: in some cases, Valtrex has been found to cause kidney disease. When taken with drugs which also carry a risk of kidney problems, the risk is compounded. These drugs include:
  • Aminoglycosides (a class of antibiotics)
  • Platinum-based chemotherapy drugs
  • Methotrexate (used to treat cancer)
  • Pentamidine (used to treat serious lung infections)
  • Foscarnet (antiviral used to prevent CMV)

Managing drug interactions

Interactions don't always mean you need to stop one of the medications. Your doctor can adjust dosages or suggest alternatives to manage these interactions safely.

It is essential to let your healthcare provider know about all the medications you are taking, as Valtrex can interact with certain drugs, including probenecid and cimetidine, which may increase the likelihood of side effects.

Dr. Caroline Fontana Lead Prescribing Doctor

Always communicate openly with your healthcare provider about your medications to ensure effective and safe treatment with Valtrex.

Storage instructions

It is important to store medication properly so that it doesn’t lose its potency.

Follow these instructions:

• keep this medicine out of sight and reach of children
• do not use this medicine after the expiry date stated on the outside of the carton
• store this medicine below 30 °C
• store this medicine in its original packaging

Disposal

Do not dispose of this medicine via wastewater or household waste. Doing so can contaminate the water supply and put people at risk of coming into contact with the medicine unnecessarily.

If you have any unused medication, take it to your local pharmacy and they will dispose of it for you.

No, both Valtrex and Valaciclovir tablets are only available on prescription. Using drugs like Valtrex when you are not supposed to can cause health complications. Because of this, you will need first to complete an online consultation with euroClinix before you purchase your herpes medication.

Ordering Valtrex through euroClinix is simple and secure. Just follow these steps:

1. Start a confidential online questionnaire from the top of this page. It will only take a few minutes to complete.
2. A UK-registered doctor will review your consultation.
3. If approved, the doctor will issue an electronic prescription.
4. A licensed UK pharmacy will send your medication in discreet packaging. The pharmacy will also share tracking information. You get free next-day delivery.

euroClinix offers ongoing support for any questions. Privacy and security are guaranteed through compliance with the relevant regulatory standards and the use of encrypted transactions.

euroClinix is a trusted online clinic that offers services in several European countries. All consultations and prescriptions are handled by our UK-registered doctors.

The process is convenient with online consultations and discreet home delivery. Our friendly customer service team is always happy to assist with any questions related to our services.

The euroClinix platform is user-friendly for managing prescriptions and reorders securely.

Choosing euroClinix ensures a trusted, professional, and supportive service to treat herpes infections. Start your journey with euroClinix today and experience our expert care.

Here is a helpful table listing the available prices of Valtrex. Buying more at one time will allow you to save on your order.

You can buy valaciclovir (Valtrex), aciclovir, or Famvir from euroClinix following an online consultation.

An alternative cold sore treatment is an antiviral cream containing aciclovir. These are topical treatments that can be bought over-the-counter, and may be preferred to oral medication in the treatment of cold sores.