Herpes Treatment: Antivirals for Outbreaks vs Suppression

There's no cure for genital herpes, but two antiviral strategies control it well: episodic therapy means a short course of pills taken at the very first sign of an outbreak to shorten it, while suppressive therapy means a daily pill that cuts how often outbreaks happen and lowers the odds of passing the virus to a partner. Which you pick depends on outbreak frequency, your partner's status, and convenience.

The three antivirals used for herpes

Herpes is caused by HSV-1 and HSV-2, and like other viral infections it's controlled but not cured: antibiotics do nothing against it, which is a key difference from a bacterial infection like gonorrhea that's wiped out with a single shot. The three drugs that work against HSV are acyclovir, valacyclovir, and famciclovir. All three block the viral enzyme HSV uses to copy its DNA, so they stop the virus from multiplying, they don't clear it from the nerve cells where it lies dormant between flares.

Not sure which side of that choice you are on? Answer three quick questions below, how often you get outbreaks, how much they affect you, and whether you have a partner to protect, and the tool points to whichever approach the CDC guidance leans toward for you. Nothing you enter leaves your browser.

Acyclovir is the oldest and least expensive, but it's absorbed less efficiently, so it's dosed more times a day. Valacyclovir is a prodrug of acyclovir, your body converts it to acyclovir, which means it absorbs better and can be taken fewer times daily, a real convenience advantage. Famciclovir works similarly with twice-daily dosing. Clinically they're comparable in how well they tame outbreaks; the choice often comes down to pill frequency and cost.

Episodic therapy: catch it at the first sign

Episodic therapy means keeping antiviral pills on hand and starting them the moment you feel a flare beginning: the tingling, itching, or burning (the prodrome) that precedes the blisters by hours. Started early, it shortens the outbreak and eases the pain; started after lesions are already crusting, it does much less. This approach suits people with infrequent or mild outbreaks who'd rather not take a daily pill. Your clinician prescribes a short, defined course taken over several days; follow the exact regimen on your label, since the dose and duration differ by drug. The CDC 2021 guidelines CDC, 2021 spell out the recommended episodic regimens for each antiviral.

The practical key is access: episodic therapy only works if the pills are already in your medicine cabinet when symptoms hit, because the early window is narrow. Many people ask for a refill so they're never waiting on a pharmacy mid-flare.

Suppressive therapy: a daily pill to stay ahead of outbreaks

Suppressive therapy means taking an antiviral every single day, whether or not you have symptoms, to keep the virus quiet. It reduces how often outbreaks happen and shortens the ones that break through: and it lowers viral shedding, which is what drives transmission to partners. The CDC lists the suppressive regimens as acyclovir 400 mg orally twice daily, valacyclovir 500 mg or 1 g orally once daily, or famciclovir 250 mg orally twice daily CDC, 2021.

One caveat worth knowing: the CDC notes that valacyclovir 500 mg once daily may be less effective than the other regimens for people who get frequent recurrences, roughly ten or more episodes a year. If you're in that group, the higher valacyclovir dose or another regimen is usually the better fit. Suppression is the standard recommendation for people with frequent or distressing outbreaks, and for anyone wanting to protect an uninfected partner.

How to choose: episodic vs suppressive

There's no single right answer: it's a judgment call based on how often you flare, who you're protecting, and what fits your life and budget. A useful way to frame it:

Many people start with episodic therapy and switch to suppression if outbreaks become frequent or a new relationship makes partner protection a priority. You can also switch back: this isn't a permanent commitment, and it's worth revisiting with your clinician once a year.

How well each strategy works

Episodic therapy reliably shortens an individual outbreak when started early, but it doesn't reduce how often outbreaks come. Suppressive therapy does both: it meaningfully cuts the number of recurrences and reduces asymptomatic shedding, the silent viral activity between flares that accounts for much transmission. That shedding matters because herpes spreads even with no visible sores: the CDC reports that HSV-2 seropositive people with no history of symptomatic herpes still have only a 50% decreased risk of genital shedding compared with those who do have symptoms, meaning the virus can be active without any warning.

For couples where one partner has herpes and the other doesn't, daily suppression plus consistent condom use is the combination that lowers transmission most. No antiviral makes transmission impossible, so it's a risk-reduction tool, not a guarantee.

Safety, resistance, and long-term use

All three antivirals are well tolerated, even taken daily for years; side effects are usually mild, like headache or nausea. Long-term suppressive use has a strong safety record, and there's no need to stop after a set period, many people stay on it indefinitely. Antiviral resistance is uncommon in people with healthy immune systems but can develop in those who are immunocompromised. Because acyclovir resistance also confers resistance to valacyclovir and famciclovir (they share the same mechanism), a resistant case needs a different drug class, foscarnet 80–120 mg/kg/day IV in divided doses until clinical resolution is the recommended option STI mgmt review. That's a hospital-level treatment reserved for genuine resistant infection, not routine outbreaks.

The biggest practical mistake isn't a drug failure: it's stopping treatment the moment you feel better, which lets outbreaks bounce right back. Take the full course exactly as prescribed.

Pregnancy and herpes

Genital herpes in pregnancy carries a small but serious risk of passing the virus to the newborn at delivery, so management is specific. The CDC notes that antiviral treatment started at 36 weeks' gestation reduces the frequency of cesarean delivery among women with recurrent herpes by diminishing outbreaks at term. ACOG likewise recommends that women with active recurrent genital herpes be offered suppressive acyclovir or valacyclovir starting at or beyond 36 weeks to decrease lesions and viral shedding at delivery ACOG. If you're pregnant and have a herpes history, tell your obstetrician early so this can be planned.

What about screening?

If you have symptoms, get a swab of an active lesion, that's the most accurate test. But routine blood-test screening for herpes in people without symptoms isn't recommended: the USPSTF advises against routine serologic HSV screening in asymptomatic adolescents and adults, including pregnant people, because false positives and the anxiety they cause outweigh the benefit USPSTF, 2016. If you do want testing for symptoms or after a known exposure, you can get tested, and it helps to know when to test after exposure so the result is reliable.

When to see a clinician

See a clinician for a first suspected outbreak (so it can be confirmed by swab and treated promptly), if outbreaks are frequent or severe enough to disrupt your life, if you're pregnant or planning to be, if you have a partner you want to protect, or if you're immunocompromised. Treatment usually looks like a short course of pills or a daily tablet, often free or low-cost at a health department or Planned Parenthood. Unlike a bacterial STI such as gonorrhea treatment, herpes has no single-shot cure, so the conversation is about ongoing management, not a one-and-done fix.

How common is genital herpes?

You're far from alone. WHO estimates that in 2020 about 846 million people aged 15–49 were living with genital herpes worldwide, more than one in five of that age group, and roughly 42 million acquire a new genital infection each year WHO, 2024. Of those, an estimated 25.6 million new HSV-2 infections occurred in 2020, with 519.5 million people living with HSV-2 WHO HSV study. Earlier 2016 modelling put HSV-2 prevalence at 491.5 million people, or 13.2% of the 15–49 age group, while an estimated 3.75 billion people had HSV-1 at any site WHO, 2016.

Keep exploring on EasySTD: which STD test you need, your risk of an STD and Genital Herpes testing.