What’s the Difference Between Cold Sores and Herpes?

By Alicia Wooldridge, MD
Medically reviewed checkmarkMedically reviewed
July 19, 2022

Cold sores are one of those things that you can feel coming on.

That distinct tingling near your lip may cause you to seek out medication to try to prevent the blister from forming. 

But if the cold sore still crops up, there’s nothing to be embarrassed about.

While cold sores are a tell-tale symptom of the herpes simplex virus, most of the time people with oral herpes contract the virus from non-sexual activity.

Plus, herpes simplex virus type 1 (HSV-1) is very common: Worldwide, two-thirds of people younger than 50 are infected.

In this article, I’ll clear up the difference between a cold sore vs herpes.

I’ll discuss the symptoms, causes, diagnosis, and treatments for a cold sore vs herpes.

I’ll also share when to see a doctor about symptoms of herpes simplex virus.

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Are Cold Sores Considered Herpes?

Cold sores (also called fever blisters) are a symptom of the herpes simplex virus, a viral infection that is often contracted through direct contact with an infected person.

HSV-1 usually causes cold sores that can spread from your lips and mouth to other parts of the body such as your eye, which, when left untreated, could lead to blindness. 

Are cold sores contagious?

HSV-1, which causes cold sores, is very contagious and easily spreads through contact with infected body fluids.

An infected person can even spread HSV-1 when they do not have cold sores or other symptoms.

Oral Herpes vs. Genital Herpes

There are two types of herpes simplex virus: HSV-1 and HSV-2.

Both can cause oral or genital herpes. However, HSV-1 most commonly causes oral herpes (and cold sores), and HSV-2 most commonly causes genital herpes.

Oral herpes generally infects the lips, mouth, and gums, while genital herpes causes sores on the genitals, thighs, and butt.

Both strains of HSV are lifelong with no cure.

After the initial outbreak of herpes infection, the virus lies dormant in your body but may pop up anytime as another sore in the same place as before.

Symptoms

Symptoms of either strain of the herpes virus can range from mild to severe, and sometimes people will have no symptoms.

Usually the first outbreak causes more intense symptoms than subsequent outbreaks.

It is also common to experience more outbreaks (called recurrences) during the first year of contracting the virus than in later years.

Cold sores 

Cold sores often begin subtly and then advance through a series of stages in about 1-2 weeks: 

  • Stage 1: About 12-24 hours before blisters appear, many people experience tingling, itching, or burning near their lips.
  • Stage 2: One or more painful, fluid-filled fever blisters crop up around the lips or sometimes inside the mouth.
  • Stage 3: Within a few days, the blisters open and ooze fluid. 
  • Stage 4: A yellow or brown crust forms on the cold sores, followed by a scab.
  • Stage 5: The scab falls off. Sometimes a new scab forms, other times the skin heals.

In a first-time outbreak, you may also experience the following symptoms:

Genital herpes

The first symptoms of genital herpes usually appear 2-12 days after exposure to the virus and generally last 2-4 weeks.

Common symptoms of genital herpes infection include: 

  • Itching or irritation in the genitals
  • Painful sores or small blisters on and around the genitals that may break open
  • Ulcers that may make urination painful

The initial outbreak is often more severe than subsequent outbreaks and may also include the following symptoms:

What Causes a Cold Sore and Herpes?

A cold sore is caused by the herpes simplex virus.

HSV-1 and HSV-2 can be transmitted in a few different ways.

You can develop cold sores if you:

  • Kiss someone infected with HSV-1. 
  • Share utensil or personal items such as lipsticks, razors, or towels with a person who has HSV-1.
  • Perform oral sex on someone who has HSV-2 on their genitals. 

You can develop genital herpes if you:

  • Receive oral sex from a person infected with HSV-1.
  • Have unprotected vaginal sex with a person who has HSV-2.
  • Give or receive anal sex with a person infected with HSV-2.

In rare cases, a mother can  transmit the herpes virus to her child during childbirth.

How Are Cold Sores and Herpes Diagnosed?

Cold sores can be mistaken for other mouth sores such as canker sores or those caused by mouth cancer or lupus.

HSV-1 can also be misdiagnosed for mononucleosis, a.k.a. the “kissing disease”.

So if you have never been diagnosed with HSV-1 and have symptoms, see a healthcare provider.

They may diagnose herpes with only a physical exam, or they may swab a sore or use a blood test to confirm the diagnosis. 

If you test positive for HSV-2, your healthcare provider may recommend testing for other sexually transmitted diseases (STDs), especially if you are going through an outbreak.

This is because open genital or mouth sores make it easier for HIV to enter your bloodstream.

Treatment 

Cold sores and genital herpes outbreaks can clear up without treatment, but certain medications and home remedies can speed up the healing process and reduce discomfort.

Cold Sores

  • Prescription medications: Oral or topical antiviral medications promote the healing of fever blisters. A doctor may prescribe acyclovir (Zovirax), valacyclovir (Valtrex), famciclovir (Famvir), or penciclovir (Denavir).
  • OTC medications: Docosanol (Abreva) or other over-the-counter ointments may shorten the duration of a cold sore or even prevent one from forming. Pain relievers such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) may also help with discomfort.
  • Home remedies: Applying a clean, cold compress directly to the sore may help relieve some pain. Additionally, lip balm with SPF can help keep lips moist and protect against sunburn, which can cause more pain.

Herpes

  • Prescription medications: Antiviral medications such as acyclovir (Zovirax) or valacyclovir (Valtrex) can help speed up the healing of a genital herpes outbreak and  suppress future outbreaks.
  • OTC medications: Over-the-counter pain reliever or topical lidocaine cream may help reduce pain during genital herpes outbreaks.
  • Home remedies: Ice packs, warm baths, and wearing loose-fitting clothing may bring some relief from the discomfort of genital sores. 
Herpes Treatment Now

Whether you’re having an outbreak or need long-term treatment, K can help. Get private, online herpes treatment today.

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When to See a Doctor 

Cold sores tend to heal without treatment within 2-4 weeks of the initial outbreak.

However, see a doctor in any of the following circumstances:

  • You have a weakened immune system.
  • The sores don’t heal within two weeks.
  • Symptoms are severe.
  • You have frequent recurrences of cold or genital sores.
  • You experience irritation in your eyes.

How K Health Can Help

Did you know you can get affordable primary care with the K Health app?

Download K to check your symptoms, explore conditions and treatments, and if needed text with a doctor in minutes. K Health’s AI-powered app is HIPAA compliant and based on 20 years of clinical data.

Frequently Asked Questions

Does a cold sore always mean herpes?
A cold sore is a symptom of oral herpes, but it does not necessarily mean you have a sexually transmitted disease. Most cases of oral herpes are caused by herpes simplex virus 1 (HSV-1) and are not transmitted by sexual contact. Instead, they emerge from exposure to someone with the virus through kissing, sharing objects, or touching contaminated surfaces.
Can cold sores be mistaken for herpes?
Cold sores are a physical symptom of oral herpes and can sometimes be mistaken for mouth sores caused by lupus, mouth cancer, thrush, celiac disease, gingivostomatitis, and more.

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

Alicia Wooldridge, MD

Dr. Alicia Wooldridge is a board certified Family Medicine physician with over a decade of experience.

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