How long does a Herpes outbreak last?

How long an outbreak lasts depends on whether it’s your first one and where it is:

• First outbreak of genital Herpes: usually 2 to 4 weeks from the first symptoms until the sores have healed.
• Repeat outbreaks of genital Herpes: usually milder, and they clear up in about a week to 10 days.
• Cold sores: most clear up on their own within 10 days.
• A first Herpes infection in the mouth: this can take 2 to 3 weeks to clear up.

Antiviral tablets can make an outbreak shorter and less painful, especially if you start them early. For a repeat outbreak, they usually shorten it by 1 or 2 days, and you may not need them.

Most outbreaks follow the same pattern:

• Tingling, itching or burning where the sores will appear, which can start before anything shows.
• Small blisters filled with fluid.
• The blisters burst, leaving red, open sores that can be painful.
• The sores crust over or scab, then heal.

Genital Herpes sores can appear around your genitals, anus, thighs or bottom. Cold sores usually appear on or around the lips. Read more in “Do Genital Herpes sores change during different stages?”

The first outbreak is usually the worst. As well as sores, it can come with flu-like symptoms, such as a high temperature, headache, aches and swollen glands, and it can make peeing painful.

Later outbreaks are usually milder and shorter, and many people feel tingling, burning or itching before the sores appear. The first outbreak you notice isn’t always your first infection. Many people catch Herpes without any symptoms, and the first outbreak can come months or years later, so it may be mild.

After a first outbreak, genital Herpes caused by HSV-2 comes back about 4 times a year on average, while genital Herpes caused by HSV-1 comes back much less often. For most people, outbreaks become less frequent and milder over time. Read more in “Why does my Herpes keep coming back?”

Herpes is caused by the Herpes simplex virus (HSV). There are two types:

• HSV-1 is far more common. It usually causes cold sores, but it can also cause genital Herpes through oral sex, and it is now the most common cause of genital Herpes in the UK.
• HSV-2 mainly causes genital Herpes.

The World Health Organization estimates that 64% of people under 50 worldwide have HSV-1, and 13% of people aged 15 to 49 have HSV-2. Having one type doesn’t protect you from the other.

HSV-1 is mainly passed on through kissing and other close contact with the mouth, including oral sex. An ordinary handshake is very unlikely to pass it on. Read more in “Oral vs Genital Herpes: what is the difference?”

Once you have Herpes, the virus stays in your body and can become active again from time to time. Common triggers include:

• being ill or run down
• stress
• strong sunlight or sunbeds
• periods
• friction from sex or tight clothing
• surgery or injury to the area
• smoking
• drinking alcohol
• a weakened immune system

Particular foods aren’t a recognised trigger. Having a new partner isn’t a trigger in itself, although friction during sex can set off an outbreak.

Yes. Herpes spreads most easily when you have sores, but it can also be passed on when there are none. Most people with Herpes have no symptoms, or symptoms so mild they don’t notice them. The virus can still be active on skin that looks normal, which is called asymptomatic shedding. It is most common in the first year after infection, especially with genital HSV-2, and happens less often over time.

To lower the risk of passing Herpes on:

• don’t have vaginal, anal or oral sex from the first tingle until the sores have completely healed
• if you have a cold sore, don’t kiss anyone or have oral sex until it has completely healed, as oral sex can give your partner genital Herpes
• use condoms at other times, which lowers the risk but doesn’t remove it
• don’t touch the sores, and wash your hands if you do

Herpes can also spread to other parts of your body, such as a finger or an eye, if you touch a sore. Read more in “Do condoms protect against Herpes?”

There’s no cure for Herpes, but you can ease the symptoms of an outbreak:

• clean the area with plain or salt water
• take paracetamol or ibuprofen for the pain
• hold an ice pack wrapped in a cloth against the sores
• put petroleum jelly or a numbing cream on the sores before you pee, or pee while pouring water over your genitals

To make outbreaks less likely, avoid your own triggers where you can. For cold sores, using a lip balm with a sun protection factor (SPF) of 15 or higher in strong sunlight can help.

Antiviral tablets, such as aciclovir or valaciclovir, can ease an outbreak and help it heal faster. They work best when started early: within 5 days of the start of a first outbreak, or as soon as you feel the first tingle of a repeat one. A doctor can prescribe them.

If you get frequent outbreaks, usually 6 or more a year, taking a lower dose every day can prevent most of them. For HSV-2, it also lowers, but doesn’t remove, the risk of passing genital Herpes on.

Antiviral cold sore creams, such as aciclovir cream, are sold in pharmacies. They work best if you use them as soon as you feel the first tingle. They aren’t recommended for genital Herpes, where tablets work better.

See a doctor if you think you have genital Herpes for the first time, as antiviral tablets work best when started early. Also see a doctor if a cold sore hasn’t started to heal within 10 days, is very large or painful, or comes with swollen, painful gums and sores in the mouth. If you have a weakened immune system, see a doctor about any outbreak, as it can be more severe and last longer.

Get urgent medical care if:

• you can’t pee at all
• you have eye pain, redness or changes to your sight, as Herpes in the eye needs urgent treatment
• you feel very unwell, for example with a severe headache and a stiff neck

Read more in “Can you get Herpes in your eye?”

If you’re pregnant and have ever had genital Herpes, tell your midwife. The risk to your baby is low if you had genital Herpes before you got pregnant, and UK guidance recommends antiviral tablets from 32 weeks to lower the chance of an outbreak at birth. If you get genital Herpes for the first time while pregnant, get medical advice straight away, as a first infection in the last 6 weeks of pregnancy carries the highest risk for the baby. If your partner has Herpes, including cold sores, and you don’t, ask your midwife about avoiding sex, including oral sex, in the last 3 months of pregnancy.

Herpes can be very dangerous for newborn babies, so don’t kiss a baby if you have a cold sore, and wash your hands before touching a newborn. Get urgent medical care if a newborn baby has a high temperature, isn’t feeding well, is floppy or hard to wake, or has sores on their skin, eyes or mouth.

The best test for Herpes is a swab taken from a sore. Take it as soon as possible, before the sore scabs over, as the test is less likely to find the virus once a sore starts to heal. If you can, have the swab taken before you start antiviral tablets.

• Herpes Simplex Type 1 and 2 (Swab): tests a swab from a sore on or around your mouth or genitals for Herpes 1 and Herpes 2, with results in 5 days. You can book it at one of our clinics or order it as a home test kit.
• Blemish Screen: if you have a sore, blister or lump on or around your genitals, it tests a swab for Herpes 1, Herpes 2, HPV and Syphilis, with results in 5 days.
• Herpes Simplex Type 1 and 2 (IgG): a blood test that can show whether you have ever caught HSV-1 or HSV-2, with results in 2 days. It is also available as a home test kit.

A blood test can take several weeks to turn positive after infection, so you may need a repeat test 12 weeks after you think you caught it. It also can’t tell you when you caught it, and an HSV-1 result can’t show whether the infection is around your mouth or your genitals. UK guidelines see blood tests as useful in certain situations, rather than as a routine check for people without symptoms. A low positive result can sometimes be a false positive, especially in people at low risk.

Not sure which test you need? Our Patient Care Team is available 24/7 on 020 7099 0955. Read more in “What is the best time to get tested for Herpes?”

Can a Herpes outbreak go away on its own?

Yes. Herpes sores heal on their own, but antiviral tablets can make an outbreak shorter and less painful, especially a first one. The virus stays in your body, so outbreaks can come back.

Can you have sex during a Herpes outbreak?

No. Avoid vaginal, anal and oral sex from the first tingle until the sores have completely healed, because that’s when Herpes spreads most easily.

What does a Herpes outbreak look like?

Genital Herpes usually causes small blisters that burst to leave red, open sores around your genitals, anus, thighs or bottom. Cold sores start as small blisters around the mouth that burst and crust over into a scab. Read more in “What does a Herpes rash look like?”

A first genital Herpes outbreak usually lasts 2 to 4 weeks, while repeat outbreaks are usually milder and clear up in about a week to 10 days. Antiviral tablets can make outbreaks shorter, and for most people they become less frequent over time.

If you have a sore and aren’t sure what it is, get tested while it’s fresh. Book a Herpes Simplex Type 1 and 2 (Swab) test at a clinic near you. Our Patient Care Team is available 24/7 on 020 7099 0955.

Not in the UK? Choose your country from the selector at the top of the page for local tests and prices.

This article originally appeared on 24 March 2023 and was last updated on 29 September 2026.

Medical review. This article was medically reviewed by Dr Steve Chapman, Doctor with a wealth of clinical experience in the field of STIs, on 11 June 2024. It is general information and not a substitute for personal medical advice.

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