What Is the Valacyclovir Dosage for Herpes? Plus, How to Stop an Outbreak

Valacyclovir hydrochloride (the generic for Valtrex^®) can reduce herpes symptoms and shorten the amount of time an outbreak lasts. But you need to take it fast — we’re talking within 24 hours of symptoms starting in some cases.

But how much should you take? The valacyclovir dosage for herpes depends if you’re taking it for cold sores or genital herpes, and the dose also depends on whether this is your first rodeo or if you’ve experienced outbreaks before.

Ahead, learn what Valtrex dosage to take and get other tips on how to stop a herpes outbreak in its tracks.

First, a quick biology lesson. Herpes is caused by the herpes simplex virus (HSV). While there are a few different types, we’re talking about two types of HSV here:

• Herpes simplex virus type 1 (HSV-1), which mostly causes oral herpes or cold sores

• Herpes simplex virus type 2 (HSV-2), which mostly causes genital herpes and is considered a sexually transmitted infection (STI)

However, if you receive oral sex from someone with HSV-1, you can get genital herpes caused by HSV-1. And vice versa. You can learn more in our guide on HSV-1 vs. HSV-2.

Some — many, in fact — lucky folks don’t get any symptoms at all, while other people get mild symptoms that could be mistaken for a pimple or ingrown hair.

But most people who get symptoms experience herpes lesions, or small blisters, which develop around the mouth, genitals, or rectum.

The virus spreads through skin-to-skin contact during sexual activity, including vaginal, anal, and oral sex. The virus can also be transmitted through kissing. 

Once contracted, HSV remains in the body for life, lying dormant in nerve cells and reactivating periodically due to triggers like stress, illness, a weakened immune system, or friction from sexual activity. 

Because herpes can be transmitted even when no visible sores are present, many people unknowingly pass the virus to their partners. 

This is why it’s important to be tested for sexually transmitted infections (STIs) and adhere to any prescribed treatments, which often include valacyclovir.

Before lesions from herpes pop up, you may experience some tell-tale signs an outbreak is coming. These are known as prodromal symptoms.

The first signs of oral HSV infection, which you may feel in the area where a cold sore is about to pop up, include:

• Tingling

• Itching

• Burning

For genital herpes, early signs include:

• Localized genital pain

• Tingling in the legs, hips, or butt

• Shooting pains in the legs, hips, or butt

You may notice these symptoms a few hours or even days before lesions appear.

During your first herpes outbreak, you might also get flu-like symptoms such as:

• Fever

• Body aches

• Headache

• Swollen lymph nodes near the infection

• Sore throat (for cold sores)

You may also get herpes symptoms that aren’t sores at all, such as:

• Genital itching

• Irritation

• Excoriations (sore red skin that starts to peel)

• Painful urination

• Lower abdominal pain

The silver lining is that the symptoms of subsequent outbreaks are usually shorter and less severe than your first. Phew.

Antiviral medications like valacyclovir, acyclovir, and famciclovir can be used to treat herpes outbreaks. Want the nitty-gritty details? Check out our guide on how valacyclovir works.

Valacyclovir is a medication approved by the Food and Drug Administration (FDA) to treat cold sores, genital herpes, herpes zoster (shingles), and chicken pox.

Unfortunately, valacyclovir can’t cure the herpes infection, but it can reduce the symptoms and how long lesions hang around.

The valacyclovir dosage for herpes will depend on factors such as what virus you’re dealing with (HSV-1 or HSV-2) and if you’ve had an outbreak before.

FYI, you can’t get valacyclovir or Valtrex over the counter. You’ll need to speak with a healthcare provider to get a prescription. They can also give you medical advice on the best valacyclovir dose for you.

A small preface here: Your recommended dose of valacyclovir is going to be whatever your healthcare provider prescribes you to prevent toxicity. Full stop.

All of the information below is based on valacyclovir’s prescribing information, but your healthcare provider will be your best source of information for dosing.

Now that that’s out of the way…

If this is your first outbreak of genital herpes, you should likely take a 1,000 milligram (mg) dose of valacyclovir twice a day for 10 days.

Treatment is most effective if you take it within 48 hours of your symptoms starting.

There’s some good science backing valacyclovir for genital herpes.

For example, studies show that valacyclovir — when delivered within 72 hours of symptoms starting — can speed up healing in people with genital herpes for the first time. If you take it more than 72 hours after the onset of symptoms, though, it’s not clear whether it helps.

A 1,000 mg tablet twice a day for 10 days can lead to:

• Lesions healing in about nine days

• Pain stopping in about five days

• Viral shedding (when your body produces infectious particles) stopping in about three days

If this is a recurrent genital herpes outbreak, you should likely take a 500 mg dose of valacyclovir twice a day for three days.

Again, you should start treatment as soon as you notice any symptoms — it’s not clear whether valacyclovir will work for recurrent episodes of herpes outbreaks if you take it more than 24 hours after your symptoms start.

Clinical trials also show that valacyclovir can help those who have had genital herpes before. 

A 500 mg dose of valacyclovir twice daily for three days can lead to:

• Lesions healing in about four days

• Pain stopping in about three days

• Viral shedding stopping in about two days

You can learn more in our guide to how fast valacyclovir works.

You can also take herpes meds daily to reduce how often herpes outbreaks occur and reduce the chances of passing the virus on to your sexual partner. This is known as suppressive therapy. It’s often recommended for people who get very painful or frequent outbreaks. According to the Centers for Disease Control and Prevention (CDC), suppressive therapy lowers genital herpes outbreaks by 70 to 80 percent in frequent cases.

For suppressive therapy, people with normal immune function should likely take a 1,000 mg dose of valacyclovir once a day. If you get nine or fewer outbreaks a year, you might be prescribed a once-a-day 500 mg dose.

People who have HIV as well may be prescribed 500 mg of valacyclovir twice a day.

The valacyclovir dosage for the treatment of cold sores (called herpes labialis) is different from the dose for genital herpes.

For oral herpes, you should take a 2,000 mg dose of valacyclovir twice a day for one day, 12 hours apart.

Just like with the genital variety, you need to act fast. You should take valacyclovir for cold sores as soon as you notice the early signs. Remember, that’s tingling, itching, or burning. Valacyclovir may not work as well if you take it once a blister develops.

Clinical studies on almost 1,900 patients with recurrent cold sores have found that valacyclovir can speed up the healing process.

When patients took valacyclovir quickly — most of them within two hours of noticing symptoms — their cold sores lasted on average one day less than the cold sores of people who didn’t take any treatment.

People receiving treatment in this study took either 2,000 mg of valacyclovir twice a day for one day or 2,000 mg of valacyclovir twice a day for one day, then 1,000 mg twice a day the next day.

The two-day treatment didn’t have any benefits beyond the one-day treatment.

Valacyclovir didn’t help those who took it when the cold sore itself had already popped up.

Taking valacyclovir (Valtrex) can significantly reduce the risk of transmitting herpes, but it does not eliminate the possibility entirely. 

Herpes is most contagious during an active outbreak when sores are present, but it can also spread through asymptomatic shedding, meaning the virus is present on the skin even without visible symptoms. 

Daily suppressive therapy with valacyclovir can reduce viral shedding by about 50 percent, especially when combined with other preventive measures like condom use and avoiding sexual contact during outbreaks. 

However, while valacyclovir reduces transmission risk, the only way to prevent spreading herpes completely is abstinence from sexual activity.

While taking valacyclovir, consider avoiding the following contraindications to maximize its effectiveness and reduce potential side effects:

• Dehydration: Valacyclovir can be hard on the kidneys and have nervous system-related side effects (especially in older people), so drink plenty of water to stay hydrated.

• Sex during outbreaks: Even with medication, herpes is highly contagious when sores are present. It can still be transmitted without visible symptoms, so safer sex practices or abstinence is important.

• Certain medications: Some drugs, like nephrotoxic medications (e.g., NSAIDs, aminoglycoside antibiotics), can increase renal impairment when taken with valacyclovir. Check with your doctor about potential drug interactions.

• Missed doses: Consistency is essential for the medication to be most effective in preventing outbreaks and viral shedding. Ask your provider what to do if you miss a dose.

• High-arginine foods: Examples include nuts, chocolate, and some seeds. While not strictly required and not backed by solid research, some people find that arginine-rich foods may trigger outbreaks, so moderation may help.

Also, if you are pregnant or breastfeeding, talk to your healthcare provider about the risk of herpes infections and taking valacyclovir (Valtrex).

When you’re hit with a genital or oral herpes flare-up, there are a few things you can do in addition to taking antiviral meds to get you through it.

• Take over-the-counter pain medication. Oral pain meds like acetaminophen, naproxen, or ibuprofen and topical meds like benzocaine and lidocaine can help reduce the pain of herpes sores.

• Take a warm bath. Sitting in warm water for 20 minutes can ease discomfort from genital herpes. Avoid soaps or fizzing bath bombs. In general, keep the area clean.

• Apply a cold compress down there. Don’t apply ice directly to your genitals. Protect your skin by wrapping an ice pack in a washcloth first.

• Wear loose-fitting clothing. Yes, that means no skinny jeans or joggers, fellas. Let the area breathe.

• Drink cold drinks or suck on a popsicle. This can help cool off painful cold sore symptoms.

• Be careful of natural remedies or wacky products. They’re not always effective. For example, you can buy devices that deliver heat to areas where you feel early cold sore symptoms. This is said to stop blisters from forming, but more research needs to be done to know if these devices are effective.

• Consider L-lysine supplements. Research suggests that a daily dose of more than 3,000 mg of L-lysine may reduce recurrence rates and improve self-reported symptoms of herpes. However, more research is needed to know for sure. Talk to your healthcare provider before taking a new supplement to make sure it’s safe for you.

• Avoid kissing or sharing bottles or cups. You can pass on the cold sore virus through saliva or by touching the sore.

How Long After Genital Herpes Treatment Can I Have Sex?

If you have genital herpes, you can pass on the virus by having sex. Avoid any sexual contact during an outbreak, and use a condom when you don’t have symptoms, as you can still pass the virus on even when you don’t have lesions.

You can learn more in our guide on having sex with herpes.

You might not be able to completely stop a herpes outbreak in its tracks. However, you can take medication to reduce the symptoms and speed up the healing process.

Here’s what you need to know:

• Keep an eye out for early symptoms. That includes tingling, itching, or burning around your lips or tingling or pain in your genitals, legs, hips, or butt.

• Take valacyclovir when you first notice symptoms. Timing is everything when it comes to stopping a herpes outbreak. You want to take valacyclovir within 48 hours of symptoms starting for your first genital herpes outbreak and within 24 hours for recurrent outbreaks. ASAP is the name of the game for cold sores, too.

• Your valacyclovir dosage will depend on what you’re taking it for. For cold sores, it might be 2,000 mg twice a day for one day. For genital herpes, it might be 1,000 mg twice a day for 10 days for initial outbreaks and 500 mg twice a day for three days for those who have had outbreaks before. Your healthcare provider will figure out the right dose with you. 

Herpes meds can be a godsend for those who feel an outbreak coming on, and valacyclovir isn’t your only option when it comes to herpes treatments. Dive deeper with our guide on valacyclovir vs. acyclovir.

If you do notice symptoms, you can speak to a licensed healthcare provider as part of our sexual health services to get herpes drugs online.