Herpes simplex

  • Overview
    Herpes simplex: After clearing, herpes simplex sores can return. When the sores return, the outbreak tends to be milder than the first outbreak.

    Herpes simplex: Overview

    Herpes simplex is a common viral infection. If you’ve ever had a cold sore or fever blister, you picked up the herpes simplex virus. Most cold sores are caused by herpes simplex virus type 1 (HSV-1). Other names for cold sores caused by HSV-1 are:

    • Oral herpes.
    • Mouth herpes.
    • Herpes simplex labialis.


    A closely related herpes simplex virus, HSV-2, causes most cases of genital herpes. But either HSV-1 or HSV-2 can cause a herpes sore on the face or genitals.

    Image used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides.

    Herpes simplex

  • Symptoms
    Herpes simplex: If a person has HSV-1, a bad sunburn can trigger a herpes simplex outbreak.

    Herpes simplex: Signs and symptoms

    Many people who get the virus that causes herpes never see or feel anything. If signs (what you see) or symptoms (what you feel) occur, a person may experience:

    • Tingling, itching, or burning: Before the blisters appear, the skin may tingle, itch, or burn for a day or so.
    • Sores: One or more painful, fluid-filled blisters may appear. Blisters break open and often ooze fluid and form a crust, before healing. The first time sores appear, they will show up between 2 and 20 days after a person has contact with an infected person. The sores can last from 7 to 10 days. Where the sores appear often varies with type:

      • Oral herpes (HSV-1): Most blisters appear on the lips or around the mouth. Sometimes blisters form on the face or on the tongue. Although these are the most common places to find oral herpes, the sores can appear anywhere on the skin.
      • Genital herpes (HSV-2): Sores typically occur on the penis, vagina, buttocks, or anus. Women can have sores inside the vagina. Like oral herpes, these sores can appear anywhere on the skin.

    • Flu-like symptoms. Fever, muscle aches, or swollen lymph nodes (glands) in the neck (oral herpes) or groin (genital herpes) are possible.

    • Problems urinating. People (most often women) with genital herpes may have trouble urinating or have a burning feeling while urinating.

    • An eye infection (herpes keratitis). Sometimes the herpes simplex virus can spread to one or both eyes. If this happens, you can have pain, light sensitivity, discharge, and a gritty feeling in the eye. Without prompt treatment, scarring of the eye may result. Scarring can lead to cloudy vision and even loss of vision.

    Herpes simplex: Outbreaks usually develop around the mouth or on the genitals, but the sores can appear almost anywhere on the skin.
    If you develop signs and symptoms of herpes simplex, you can expect to have these for as long as listed below:

    • Oral (mouth) herpes: 2 to 3 weeks
    • Genital herpes: 2 to 6 weeks (the first outbreak)

    Images used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides. 

    Herpes simplex
  • Causes

    Herpes simplex: Who gets and causes

    Who gets herpes simplex?

    Most people get HSV-1 (herpes simplex type 1) as an infant or child. This virus can be spread by skin-to-skin contact with an adult who carries the virus. An adult does not have to have sores to spread the virus.

    A person usually gets HSV-2 (herpes simplex type 2) through sexual contact. About 20% of sexually active adults in the United States carry HSV-2. Some people are more likely to get HSV-2. These people:

    • Are female.
    • Have had many sex partners.
    • Had sex for the first time at a young age.
    • Have (or had) another sexually transmitted infection.
    • Have a weakened immune system due to a disease or medicine.


    What causes herpes simplex?

    Herpes simplex viruses spread from person to person through close contact. You can get a herpes simplex virus from touching a herpes sore. Most people, however, get herpes simplex from an infected person who does not have sores. Doctors call this “asymptomatic viral shedding.”

    How people get herpes around their mouth
    A person with HSV-1 (herpes simplex type 1) can pass it to someone else by:

    • Kissing.
    • Touching the person’s skin, such as pinching a child’s cheek.
    • Sharing objects such as silverware, lip balm, or a razor.


    How people get herpes on their genitals
    You can get genital herpes after coming into contact with HSV-1 or HSV-2. Most people get genital herpes from HSV-2, which they get during sex. If someone has a cold sore and performs oral sex, this can spread HSV-1 to the genitals — and cause herpes sores on the genitals.

    Mothers can give the herpes virus to their baby during childbirth. If the baby is born during the mother's first episode of genital herpes, the baby can have serious problems.

    What happens once you have HSV-1 or HSV-2?
    Once a person becomes infected with a herpes virus, the virus never leaves the body. After the first outbreak, the virus moves from the skin cells to nerve cells. The virus stays in the nerve cells forever. But it usually just stays there. In this stage, the virus is said to be dormant, or asleep. But it can become active again.

    Some things that can trigger (wake up) the virus are:

    • Stress.
    • Illness.
    • Fever.
    • Sun exposure.
    • Menstrual periods.
    • Surgery.

    Herpes simplex
  • Treatment

    Herpes simplex: Diagnosis and treatment

    How do dermatologists diagnose herpes simplex?

    During an outbreak, a dermatologist often can diagnose herpes simplex by looking at the sores. To confirm that a patient has herpes simplex, a dermatologist may take a swab from a sore and send this swab to a laboratory.

    When sores are not present, other medical tests, such as blood tests, can find the herpes simplex virus.

    How do dermatologists treat herpes simplex?

    There is no cure for herpes simplex. The good news is that sores often clear without treatment. Many people choose to treat herpes simplex because treatment can relieve symptoms and shorten an outbreak.

    Most people are treated with an antiviral medicine. An antiviral cream or ointment can relieve the burning, itching, or tingling. An antiviral medicine that is oral (pills) or intravenous (shot) can shorten an outbreak of herpes.

    Prescription antiviral medicines approved for the treatment of both types of herpes simplex include:

    • Acyclovir
    • Famciclovir
    • Valacyclovir


    Taken daily, these medicines can lessen the severity and frequency of outbreaks. They also can help prevent infected people from spreading the virus.


    The first (primary) outbreak of herpes simplex is often the worst. Not all first outbreaks are severe, though. Some are so mild that a person does not notice. When the first outbreak of genital herpes is mild and another outbreak happens years later, the person can mistake it for a first outbreak.

    Some people have 1 outbreak. For others, the virus becomes active again. When they have another outbreak, it is called a recurrence. These tend to be more common during the first year of infection. Over time, the outbreaks tend to become less frequent and milder. This is because the body makes antibodies (defenses) to the virus.

    Serious complications rarely occur in healthy people with herpes simplex. They occur most often in unborn babies, newborns, and people who have a long-term illness or weak immune system. If you have cancer or HIV/AIDS, or you had an organ transplant, seek medical help right away if you have signs or symptoms of a herpes infection.

    Herpes simplex
  • Tips

    Herpes simplex: Tips for managing

    There are things you can do at home to help manage herpes sores.

    Relieve discomfort

    The following can help:

    • Apply medicine that you can buy without a prescription, such as benzocaine and L-lysine, to the blisters.
    • Put ice on the blisters.
    • Avoid things that could trigger another outbreak, such as stress and getting a sunburn.


    Avoid spreading the virus

    The following may reduce the risk of spreading the herpes simplex virus:

    Oral herpes (herpes simplex type 1)
    If you have sores on your face:

    • Do not kiss anyone.
    • Do not have oral sex.
    • Do not share items such as silverware, cups, towels, and lip balms.


    If you have tingling, burning, itching, or tenderness where you had a herpes sore, keep that area of your body away from others.

    You can prevent spreading the sores to other parts of your body by:

    • Washing your hands after touching a cold sore.
    • Using a cotton-tip swab to apply herpes medicine to a cold sore also helps.


    Genital herpes (herpes simplex type 2)
    When you have sores or symptoms do not have sex with uninfected partners.

    • If you do not have sores or symptoms, use a latex condom to lower the risk of spreading the virus. You should know that even with a condom, it is possible to spread the virus if it lies on nearby skin that the condom does not cover.
    • If you are pregnant tell your doctor if you or your partner has genital herpes. You may need to take medicine at the end of your pregnancy to prevent passing the virus to your baby.

    Herpes simplex