Are Cold Sores An STD (Sexually Transmitted Disease)?

Have you considered clinical trials for Cold sores?

We make it easy for you to participate in a clinical trial for Cold sores, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

What are cold sores?

Cold sores are itchy or painful, fluid-filled blisters that typically form on or near your lips. They are also called "fever blisters." They are small and typically clear up on their own within ten days, although they can be quite annoying in the interim.

Prevalence and causes

Cold sores are usually caused by the HSV-1 virus, which is highly prevalent. Most people infected with this virus are asymptomatic and typically pick it up in early childhood from physical contact with others.

In some cases, they can be caused by the HSV-2 virus. Both of these viruses are forms of the herpes simplex virus. HSV-2 typically causes genital herpes, but you can get it around your mouth if you give oral sex to somebody who is infected.

Signs and symptoms of cold sores

The classic symptom is the cold sores themselves, which are typically preceded by a tingling sensation. If it is your first outbreak, you may also experience a low-grade fever and swollen lymph nodes. Cold sores typically go away but can recur. The virus stays in your system your entire life.

Risk factors of cold sores

Currently, there is no cure for HSV-1, so those infected will have the virus for the duration of their lives. Exposure often occurs during childhood. Adults who carry the virus may be unaware of its presence in the body, as many infected people are asymptomatic. 

Hormonal changes such as the menstruation cycle and pregnancy can lead to cold sore outbreaks.  

You are at a higher risk of developing complications from the virus if you have a weakened immune system from conditions and treatments such as HIV/AIDS, atopic dermatitis (eczema), chemotherapy for cancer, or anti-rejection drugs for organ transplants.

Do cold sores mean you have an STD?

Genital herpes is one of the most common STDs in the world. The vast majority of people with genital herpes have no symptoms. When they do, the symptoms are similar, with inflamed skin and small blisters.

However, HSV-1 is not considered an STD. It is transmitted through simple contact and things like sharing razors and towels. While it can also be transmitted by kissing, the primary cause of transmission is not sexual activity.

That said, sometimes cold sores can be caused by HSV-2. In that case, they typically are transmitted by sexual activity, specifically oral sex with somebody infected with HSV-2. This is, however, a lot rarer.

Can cold sores be sexually transmitted?

Although cold sores are not a sexually transmitted infection (STI), you can give your partner HSV-1 during sexual activity due to close contact and kissing. You should not have sex or engage in an intimate activity if you have an active cold sore outbreak.

Is there any similarity between cold sores and oral herpes?

They are essentially the same, but oral herpes is more likely to refer to infection with HSV-1. The symptoms, however, are similar.

Can cold sores cause chlamydia?

No. Chlamydia is a totally different disease. It is caused by bacteria and has no connection to cold sores.

What are the common STDs and how are they different from cold sores?

The most common sexually transmitted diseases other than genital herpes are:

  • Chlamydia, which causes abnormal discharge, a burning sensation when peeing, and sometimes pain and swelling in the testicles

  • Gonorrhea, which can affect the genitals, rectum, or throat. It often has no symptoms, but it can cause a painful or burning sensation when peeing, increased vaginal discharge and spotting between periods, a white, yellow, or green discharge from the penis, and pain and swelling in the testicles.

  • Hepatitis, which causes damage to the liver

  • Human papillomavirus, which typically causes no symptoms (although some strains cause genital warts) but increases your risk of cervical and anal cancer


If you have sores in your mouth or genitals, your doctor can help determine what is causing them.

How are cold sores diagnosed?

Oral cold sores are typically diagnosed through visual inspection. To the trained eye, the blisters are quite distinctive. Your doctor may swab a blister to confirm the diagnosis.

Prognosis of cold sores

Once you have herpes simplex virus, it stays there for life. However, many people never even have cold sores. Of those who do, some only have them once, while others might experience repeated outbreaks. Outbreaks tend to become less frequent as you get older.

Cold sores typically go away within ten days. Your doctor can prescribe antivirals to help them clear up faster if needed.

HSV infection can be dangerous to newborns, so if you are pregnant, your doctor may recommend a course of antivirals. If you have active genital herpes close to your delivery time, your obstetrician will likely recommend a C-section to avoid exposing the baby.

Treatment and medication options for cold sores

The following treatment options are typically prescribed:

  1. Antiviral medication. This helps slow down the reproduction of herpes simplex. It can be taken orally or applied as a cream directly to the sore. Antivirals can reduce the duration of the outbreak and lower your risk of transmitting it to others.

  2. Oral or topical painkillers to relieve symptoms

Placing ice on the sores or sucking on ice can also relieve symptoms substantially.

How to prevent cold sores

Cold sores are best prevented by avoiding herpes simplex infection. You can avoid it by not sharing towels, razors, lipstick, etc., with others, especially outside your household. It’s also best to avoid skin contact or kissing, especially with newborns or strangers.

You should not have unprotected sex with multiple partners. Using a condom every time you have sex substantially reduces the risk of all STDs. It is also important not to share sex toys. 

As you can get HSV-2 from somebody with genital herpes, always use a condom or a dental dam when having oral sex. You can make a dental dam out of a condom if you cannot find them. 

Staying healthy and managing stress can prevent outbreaks. Using sunscreen on your face can also help reduce the number of cold sores you get. Outbreaks are often associated with respiratory infections such as colds.

You can prevent passing on cold sores by avoiding intimate contact with others during an outbreak and by being especially careful to avoid physical contact with infants.

The lowdown

Cold sores are not an STD. They can sometimes be transmitted during sexual activity, especially kissing, but are primarily transmitted through non-sexual skin-to-skin contact, typically in early childhood. They are usually not serious, but they are annoying, and your doctor can give you medication to clear them up faster.

Have you considered clinical trials for Cold sores?

We make it easy for you to participate in a clinical trial for Cold sores, and get access to the latest treatments not yet widely available - and be a part of finding a cure.

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