Usually, oral herpes (cold sores) is caused by HSV-1 and genital herpes is caused by HSV-2. But it is possible for HSV-1 to cause genital herpes and HSV-2 to cause cold sores.

There is really no way to tell by appearance alone whether an outbreak is caused by HSV-1 or HSV-2. At the same time, herpes sores may not be immediately recognized when they first appear. Or, they may be mistaken for other infections like canker sores or shingles.

This article describes the symptoms of herpes and how and where this common viral infection causes outbreaks. It also explains how herpes is treated and lists the various conditions that are similar in appearance to oral or genital herpes.

Where Herpes Can Occur on the Body

Painful blisters are the classic sign of a herpes infection. The rash may be preceded by itching, numbness, or tingling or burning sensations several days beforehand.

A classic herpes outbreak usually involves one or more blisters that start as small, red bumps. They then rapidly develop into fluid-filled blisters that sometimes merge into a larger blister.

Herpes blisters commonly erupt, leaving a painful ulcer with raised edges. The sores can ooze and crust over. Severe outbreaks can cause scarring.

Oral and genital herpes usually develop in the following ways:

Oral herpes is typically caused by HSV-1. It causes blisters, sometimes referred to as fever sores or cold sores, in or around the lips and mouth. Sometimes the blisters will form elsewhere on the face or tongue. The sores usually last two to three weeks with each outbreak. Genital herpes is typically caused by HSV-2. The sores usually develop on the penis, around or inside the vagina, or on the buttocks or anus. Sores can form on other areas of the skin as well. The first outbreak can last two to six weeks. Subsequent outbreaks tend to be less severe and shorter-lasting.

But, not every case of oral herpes involves HSV-1, and not every case of genital herpes involves HSV-2. This is because the virus is highly transmissible.

For example, if you touch a genital herpes sore and then the mouth, you can get oral herpes. If you have an oral herpes sore and perform oral sex on someone, that person can get genital herpes.

This is why it is important to avoid sexual contact during a herpes outbreak. If you have a cold sore, avoid performing oral sex on a partner or touching the sore. If you touch a sore, wash your hands immediately with soap and water.

In addition to a rash, oral herpes may be accompanied by:

HeadacheFatigueNauseaDizzinessSwollen lymph nodes in the neck

In addition to a rash, genital herpes can cause:

Fever Headache Muscle aches Fatigue Swollen lymph nodes in the groin Difficulty urinating Pain with urination

When you get herpes, the virus will always live in your body and does not go away.

Different things can trigger an outbreak including emotional stress, an acute illness, fever, trauma, surgery, sun exposure, and menstrual periods. Some outbreaks have no known cause.

How Herpes Is Treated

There is no cure for herpes, but there are antiviral drugs that may lessen the duration or severity of an outbreak. Antiviral drugs are those used to treat viral infections. As a rule, antiviral treatment is most effective when it is started at the first signs of an outbreak.

The treatment can vary by the location of the sores and other factors:

Oral herpes can be treated with Zovirax (acyclovir), Famvir (famciclovir), or Valtrex (valacyclovir). The antiviral medications are taken by mouth. The course of treatment can range from one to seven days. Genital herpes can be also be treated with Zovirax, Famvir, or Valtrex. In addition to tablets, acyclovir can be delivered by injection or applied to the sore as an ointment. Famvir and Valtrex are taken by mouth. The course of treatment varies by whether it is a first or subsequent outbreak.

You can help soothe a genital herpes outbreak by sitting in a warm bath. A cold compress placed against the rash for 10 to 15 minutes several times daily may also help.

Avoid eating spicy or acidic foods when you have a cold sore. You can also use over-the-counter (OTC) topical anesthetics like lidocaine to numb the sore; just be sure to wash your hands immediately after.

OTC pain killers like Tylenol (acetaminophen) or Advil (ibuprofen) can also help relieve pain for both oral and genital herpes.

Conditions That Look Like Herpes

Not every rash that looks like herpes is herpes. There are other infections that cause painful blistering (or blister-like) rash. These include:

Aphthous stomatitis: Also known as canker sores  Dermatitis herpetiformis: An intensely itchy, blistering skin rash that affects people with celiac disease Herpangina: A viral illness caused by the Coxsackie virus that leads to mouth sores Herpes gladiatorum: A type of herpes virus common among athletes that is passed through skin-to-skin contact Herpes zoster: Also known as shingles Syphilis: A sexually transmitted disease that typically causes a single painless ulcer on the genitals or anus

Summary

Herpes is an outbreak of painful blistering rash caused by the herpes simplex virus. Oral herpes is usually caused by herpes simplex virus 1 (HSV-1), while genital herpes is usually caused by herpes simplex virus 2 (HSV-2). Even so, HSV-1 can sometimes cause genital herpes, and HSV-2 can sometimes cause oral herpes.

Herpes can be treated with antiviral drugs. They do not cure herpes but may lessen the severity or duration of an outbreak if started early.

Other infections that mimic herpes include canker sores, shingles, syphilis, dermatitis herpetiformis, herpangina, and herpes gladiatorum.

A Word From Verywell 

If you believe that you are experiencing a herpes outbreak, see your healthcare provider as soon as possible so that treatment can be prescribed if needed. This is especially important if you have a compromised immune system. Avoid touching the rash or exposing others to the sores.

Finger swelling and painSores or blisters on fingerIrritated skin that turns red and darker than your regular skin tone