How to Treat a Cold Sore

Last Updated July 2021 | This article was created by familydoctor.org editorial staff and reviewed by Robert "Chuck" Rich, Jr., MD, FAAFP

Cold sores (also called fever blisters) are small, blister-like, fluid-filled lesions that usually appear around the border of the lips. They also may appear on other areas of your face, such as your chin or nose. Cold sores are caused by a virus called herpes simplex (HSV). They are very common and also very contagious.

Even though they are called cold sores, they have nothing to do with having a cold. You catch a cold sore by coming into close contact with someone who has a cold sore, such as by kissing. Also, not everyone who comes into contact with the virus will get a cold sore. For these people, the virus just never becomes active. But the majority of people who are exposed to a cold sore will have some sort of reaction. It may be that they get one cold sore and never have another. Or they may have cold sore outbreaks several times a year.

Because cold sores are caused by a virus, you cannot “cure” them. Thankfully, there are treatments and medicines that can help manage outbreaks when you get them.

Path to improved health

Often, the first symptom of a cold sore is a tingly feeling. This may happen 24 to 48 hours before the cold sore actually appears. When it does appear, it’s a bump that evolves into a blister that weeps and oozes. Then the blister crusts over and begins to heal. A typical outbreak lasts a week or two without treatment.

Treatments help to manage outbreaks range from over-the-counter (OTC) creams to prescription drugs to home remedies that include ice packs and aloe vera gels. Which you choose will depend on how many outbreaks you have and what works best for you.

Prescription medicines

If you have several outbreaks a year, you should see your family doctor. They will work with you on a treatment plan that may include prescription antiviral medicine. Oral antiviral medications include:

  • Acyclovir (brand name: Zovirax)
  • Famciclovir (brand name: Famvir)
  • Valacyclovir (brand name: Valtrex)

These medicines not only help speed healing, they also may prevent future outbreaks.

Your doctor may also prescribe you a numbing gel if your cold sore is painful.

OTC treatments

If your outbreaks aren’t as severe or frequent, an OTC medicine should help soothe and heal your cold sore. There are a variety of OTC creams, gels, patches, lip balms, and even lasers designed to minimize symptoms and shorten the cold sore cycle. A small sampling of popular products include:

  • Docosanol (brand name: Abreva) is an FDA approved cream safe for people 12 years of age and older. If you begin using it at first tingle, it can shorten healing time. It also helps minimize symptoms.
  • Zilactin Cold Sore Gel relieves pain and promotes healing with an active ingredient of 10% benzyl alcohol. The gel creates a protective barrier over your cold sore.
  • Orajel Cold Sore Patented Treatment is a liquid treatment with touch-free applicator. It cleans the affected area and provides pain relief.
  • Mederma cold sore patch uses hydrocolloid gel to boost recovery and reduce scab formation.
  • Compeed Cold Sore Patch conceals your cold sore while it heals it. The patch also helps prevent speading your cold sore to others.
  • Laser technology is the latest—and priciest—treatment to enter the market. The Virulite Invisible Light Electronic Cold Sore Treatment Device is FDA approved to treat your cold sore at home. Treatments may result in clearing cold sore in a matter of days.
  • Acetaminophen (brand name: Tylenol) and ibuprofen (brand name: Advil) both help relieve cold sore pain.

Home remedies

There are many home remedies for treating a cold sore. Some may be effective. However, there is no medical evidence that these methods can shorten healing time or provide pain relief.

  • Aloe vera gel
  • Vitamins C and E
  • Tea tree oil
  • Peppermint oil
  • Lemon balm
  • Vanilla extract
  • Tea bag
  • Ice

Whichever treatment you choose for your cold sore, know that it has the best chance of working if you start it during the tingling stage.

Does a having cold sore mean I have a sexually transmitted infection?

Having a cold sore does not mean that you have a sexually transmitted infection (STI). Most cold sores are caused by herpes simplex virus type 1 (HSV-1). Genital herpes (a type of STI) is typically caused by HSV-2. However, it is possible to transmit HSV-1 from a cold sore to the genital area during oral sex. In short, it is possible to get genital herpes from a cold sore from oral sex.

Can I prevent a cold sore?

Cold sores cannot always be avoided, but you may be able to help prevent them by treating them as at the very first sign of a cold sore (usually the tingling stage). You also can try to avoid known cold sore triggers (some of these are unavoidable).

  • Sunlight
  • Stress
  • Hormones
  • Fatigue
  • Fever
  • A weak immune system or changes in your immune system

Wearing sunscreen and proactively managing stress may help. Ways to reduce stress include exercising, meditating, and doing things you enjoy each day. You should also try to get 7 to 8 hours of sleep each night.

Things to consider

Once you have the cold sore virus (HSV), you have it for life. You may be reminded of it when a cold sore pops up. Or you may never really know it is there. The good news is that cold sores seem to become less frequent as you get older.

When you have a cold sore, do not pick at it or it can spread to other people or even to other parts of your body. If you touch your genitals after touching your cold sore you could develop genital herpes. So, if you have a cold sore, be sure to wash your hands if you touch it. Don’t kiss anyone while you have a cold sore or share eating utensils with them. Don’t give or receive oral sex when you have a cold sore. When your cold sore it gone, replace your toothbrush.

Questions to ask your doctor

  • What is the best way to treat my cold sore?
  • Is there any way to minimize my number of cold sore outbreaks?
  • When is my cold sore most contagious?
  • Can I transmit HSV-1 even when I don’t have a cold sore?
  • What’s the best way to keep my family members from catching HSV-1 while I have a cold sore?

Resources

National Institutes of Health, MedlinePlus: Cold Sores

National Institutes of Health, MedlinePlus: Herpes – oral