Valtrex For Shingles: Dosage, Effectiveness, And Side Effects

One of the most challenging aspects of a shingles diagnosis is managing the pain, discomfort, and sensations accompanying the outbreak of sores and blisters on the skin. The pain is manageable and tolerable for some people, but it can be debilitating and severe for others. 

Shingles can be very painful for aging populations as it is often described as far more uncomfortable than a chickenpox infection which is more common in younger age groups. 

Valtrex is an antiviral medication that can help an individual with shingles overcome pain and skin lesions more quickly.

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Researchers are studying thousands of new treatments and you could be a part of finding a cure while accessing the newest treatments for Shingles.

Is it worth taking Valtrex for shingles?

Valtrex should be taken as soon as possible after the onset of symptoms for best results. Its efficacy has been proven with one study observing a significant decrease in pain in the test group.¹

After a shingles diagnosis, you must consult your doctor to decide whether Valtrex is right for you. Discuss any possible allergies, side effects, current prescriptions that may cause interactions, and the timeline of your symptoms. For the best possible effect on your symptoms, the timing of the initial dose of Valtrex matters.

What is Valtrex, and how does it work?

Valtrex is a brand of generic medication known as valacyclovir. It is an antiviral medication used for various conditions, including for the treatment of the herpes zoster virus, also known as shingles. This medication must be prescribed by a doctor and is not available over the counter. 

Valacyclovir treats shingles by helping to shorten the symptoms and pain from the blistering that accompanies the illness. People who take a course of Valtrex for shingles are more likely to see their skin lesions resolve more quickly and experience less pain than those who do not take the medication.

Is valacyclovir the same as Valtrex?

Yes, Valtrex is the brand name for valacyclovir, a generic antiviral prescription.

How effective is Valtrex for shingles treatment?

Treatment with Valtrex can help significantly reduce the uncomfortable symptoms of shingles. In a study conducted by researchers, valacyclovir not only lessened the pain but helped more patients going through shingles infections.¹

Valacyclovir outcomes were much better than those taking famciclovir. Valacyclovir is considered by doctors an effective treatment for herpes zoster when taken in the first days following symptoms. It also has little to no serious side effects for most people. 

Shingles explained

The same varicella virus that causes chickenpox is the culprit for a shingles infection. However, when you develop shingles, you do not catch it from another person. Rather, it is the varicella virus that has lived inside your body that reactivates and causes your shingles illness — either through vaccination or prior chickenpox infection.

Anyone can develop shingles at any age if they have been exposed previously to the varicella virus. Still, it is most common in older populations as the strength of the immune system wanes over time. It is estimated that in the US, approximately 1 in 3 people will develop shingles in their lifetime.²

Shingles is not usually life-threatening, with fewer than 100 deaths per year. However, it can cause very painful lesions on the skin of individuals with the illness. In some cases, it can cause serious complications depending on your health risks.³


When a person develops shingles, the most difficult aspect is often the blisters that emerge on the skin, the pain associated with the development of the blisters, and the process of healing during the illness. The pain from shingles can begin even before lesions on the skin appear. At first, you may feel burning, slight pain, and itchiness in a concentrated area of your body, such as your face or torso.

As the days go on, you will then begin to notice redness and blistering of the skin with fluid beneath the affected area. The blisters contain the active particles of the virus. The virus can spread to others who have not previously had exposure to the varicella virus and, in turn, can cause a chickenpox infection. 

The blisters and lesions also cause the most discomfort and pain for individuals with the illness. The time it takes to fully heal from the blisters will vary, but in most cases, the healing process can take a few weeks to one month.


The cause of a shingles infection is the varicella virus that lives within your body. You cannot get shingles if you have not previously been exposed to this virus. 

Past exposure to the varicella virus is through vaccination or a chickenpox infection. The virus lives dormant in your body for a long time, and at some point, a trigger will cause it to reactivate. What exactly triggers a shingles outbreak in a particular individual is unknown, but those with weakening immune systems are often at the highest risk of a shingles infection.

Risks and complications

Shingles is not commonly a deadly illness; it is most known for its debilitating pain and discomfort during the illness. However, some complications can affect an individual's life due to a shingles infection and, in some cases, can cause permanent damage.

Vision damage

Blisters or rashes from shingles that occur on the face and on the eyes can risk damage to your eyesight. This serious complication can arise and require prompt medical attention and intervention.

Nerve damage

Postherpetic neuralgia is the most common complication in individuals developing shingles. This condition arises following a shingles infection.⁴

An individual will continue to feel pain as if the blisters were still there, but the skin has healed. This damage may have occurred to the underlying nerves of the skin and require treatment to help manage the pain and lessen the effects of this often long-term consequence.

How long does it take for Valtrex to work for shingles?

The typical course of treatment with Valtrex for a shingles infection is one week long. The medication is given at evenly spaced intervals each day for seven days. 

The ideal time to begin treatment with Valtrex is as soon as symptoms of shingles begin to develop. The window of time that provides the best possible efficacy for the medication to work is within 72 hours of when the symptoms of shingles begin to appear and become noticeable to you. 

Within a few days, you should begin to feel better, the pain may be less, and the blisters on your skin will begin to heal, although it can take a bit longer for the lesions on your skin to fully heal.


Although Valtrex is safe in most instances, some individuals should avoid taking the medication. You must discuss with your doctor beforehand whether Valtrex is safe for you.

Speak with your doctor about Valtrex treatment if you:

  • Are pregnant or nursing

  • Have a condition that causes a weakened immune system

  • Have kidney disease or have had a kidney transplant

What is the proper Valtrex dosage for shingles treatment?

Valtrex for shingles is given as an oral tablet of 1,000mg per dose. The course of treatment for a shingles outbreak in a patient is usually three doses per day for seven days. This amounts to 3,000mg daily spread out over three evenly timed intervals to maintain a steady medication intake during the initial stage of a shingles infection.


Shingles is rare in children, although it can occur in kids with weakened immune systems. Valtrex can be used to treat shingles if a child develops the condition. It is also a treatment option for children contracting chickenpox from the varicella virus. 

There is not a single standard dosage of Valtrex for children. Instead, a doctor will determine the appropriate dose based on the condition and the child's weight to ensure safety and effectiveness.

Adults and elderly

The standard dose of Valtrex is a treatment period of 1,000mg three times a day for seven days. However, there may be instances where a doctor may prescribe a longer regimen depending on your illness and the risk of serious complications.

How should I take Valtrex?

You should take Valtrex for the full course of treatment prescribed by your doctor and avoid missing doses to ensure the medication works to fight the virus. 

In shingles cases, the treatment will typically last for seven days. Even if you begin to feel better and your symptoms have improved, you must complete the regimen to ensure that the illness resolves and that you do not prolong the active stage of the virus.

You may take Valtrex while eating, but it is not necessary. It is recommended, however, that when taking valacyclovir, you drink sufficient water and remain hydrated at all times to reduce the impact on your kidney functions.

What happens if I miss a dose of Valtrex?

If you forget to take a dose of Valtrex, it is best to take it as soon as possible if too much time has not passed. However, if you are closer to the time of your next dose, it is best to skip the missed dose altogether and continue the medication as directed at the time of the next dose.

Side effects of Valtrex for shingles

Most people that take valacyclovir or Valtrex will experience few side effects, and serious side effects are rare. For those that experience side effects, it may be short-lived. However, if the effects of the medication persist and are interfering with your day-to-day life, you should speak with your doctor as soon as possible.

Common side effects of Valtrex include:

  • Gastrointestinal discomfort or distress

  • Headache

What are the chances for serious side effects of taking Valtrex for shingles?

In some cases, an individual taking Valtrex for shingles may experience potentially dangerous side effects from the medication. Allergic reactions leading to anaphylaxis due to valacyclovir or any of its ingredients are an emergency. 

If you feel any symptoms of anaphylaxis when taking the medication, call 911 and get help immediately. Anaphylaxis symptoms due to an allergic reaction to Valtrex can include shortness of breath, chest tightening, feeling of doom, hives outbreak, and itchiness or swelling of the throat, eyes, tongue, or around the mouth.

Additionally, in some individuals, Valtrex can cause distressing symptoms that may indicate a serious risk to your health if you continue to take the medication. 

The following are symptoms that warrant an immediate call to your medical provider:

  • Feeling agitated, confused, or shakiness

  • Seizure-like symptoms

  • Hallucinations

  • Severe stomach pain

  • Blood in urine

  • Fever

  • Severe fatigue

What are the long-term effects of taking Valtrex daily?

Fortunately, Valtrex for the treatment of shingles is limited to a one-week course of the medication in most patients. There are medical conditions for which Valtrex is used long-term and results in only a small risk to certain individuals.

Drug interactions with Valtrex

Combining Valtrex with certain other medications can cause you harm or put you at risk of developing certain symptoms and conditions. However, due to its classification as an antiviral medication, you should not take another antiviral medication simultaneously as Valtrex, particularly acyclovir. 

Discuss what other medications you are taking with your doctor to ensure that taking Valtrex is safe for you.

The lowdown

If you think you may have shingles, contact your doctor to discuss your symptoms and whether or not you may be eligible to take Valtrex. This will help you shorten the severity and duration of your shingles infection. 

Remember that antiviral medications such as Valtrex are most effective when taken at the onset of symptoms, usually within 72 hours of the first appearance of symptoms.

Curious about clinical trials for Shingles?

Researchers are studying thousands of new treatments and you could be a part of finding a cure while accessing the newest treatments for Shingles.

Discover which clinical trials you are eligible for

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Have you taken medication for Shingles?
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