Yes, Cold Sores Are Contagious, but Here's How to Avoid Them

If you occasionally experience cold sores, you're not alone. According to Lauren Eckert Ploch, MD, a dermatologist based in Augusta, GA, approximately 50 percent of the adolescent and adult population in the US has antibodies to this virus. Don't be quick to panic! While there is technically no cure for cold sores, the good news is that they are usually not serious and tend to clear up within a couple of weeks. They are also fairly easy to prevent, so being proactive can really help avoid those pesky spots.

Cold sores, also known as fever blisters, are small blisters that often form around the mouth. According to the American Academy of Dermatology (AAD), more than half of Americans ages 14 to 49 carry the herpes simplex virus that causes cold sores, and most people catch the virus as children. The virus is passed either through skin contact or through the saliva of an infected person. Even after an outbreak clears up, the virus stays in your body, which means you will likely experience outbreaks again in the future. According to Ploch, the HSV 1 virus often does not cause outbreaks after the initial infection. "Many people have antibodies to the virus (meaning that they've been exposed and infected), but they never get cold sores," Ploch said. "You're more likely to develop a cold sore during times of stress and with sun exposure."

The virus that causes cold sores is contagious while cold sores are present and until they have scabbed over. The virus can be serious if passed to a person with eczema or a compromised immune system, so it's important to take precautions to prevent passing it along to these people. "The virus can be spread easily through fluid from a cold sore during an outbreak," Ploch said. "However, it's important to know that our skin can shed the virus even when it's healthy and no cold sores are present."

According to the AAD, once you have the virus, cold sore triggers include stress, fatigue, hormonal changes, illness such as cold or flu, and injury such as a cut to the lip. "Sun exposure is a huge risk factor," Ploch said. "Many of my patients report developing cold sores after spending time in the sun."

Although most cold sores heal on their own, dermatologists sometimes recommend a prescription oral antiviral medication to shorten the duration of the outbreak. "I often prescribe acyclovir or valacyclovir to patients. These prescriptions can decrease the length of time that the cold sore is present," Ploch said. You can also apply ice or a cold compress or take an anti-inflammatory medication such as ibuprofen to lessen any pain, but this will not heal a cold sore. "It's also important to wear sunscreen daily, especially during outbreaks. Repetitive sun exposure can lead to more cold sores," she said.

To prevent yourself from becoming infected with the virus, Ploch advises avoiding kissing anyone with an active cold sore, as kissing can spread the virus. She also recommends avoiding sharing utensils and cups. On a similar note, if you're the one infected and experiencing an outbreak, you can prevent passing the virus to someone else by taking these same precautions and by avoiding touching your cold sores and immediately washing your hands when you have touched them.

If a lesion is not significantly improved within two to three days, see a physician, Ploch said. "I've seen several cases where patients assume they've just had a cold sore for a month, but it ends up being an unrelated squamous cell carcinoma of the lip (from previous sun exposure)."