Hereโs how to treat cold sores, and whether you can prevent them.
What causes cold sores?
The herpes virus is โvery contagiousโ, said Dr Dean Blumberg, chief of paediatric infectious diseases at UC Davis Health. You can pick it up through close contact with someone who is infected, such as through kissing or sharing food or drinks.
And itโs not always easy to tell whether someone is contagious, Blumberg said. People can transmit oral herpes without a visible cold sore.
If you do become infected, you might not develop a cold sore right away or even at all, Blumberg added. It could take years before you have an outbreak, Johnston said, or maybe you never get one.
Once you start getting cold sores, however, the virus can cause outbreaks throughout your life. The frequency varies from person to person, Johnston said. Some people get one cold sore a year; others get them multiple times a year.
Whatโs the best way to treat cold sores?
Most cold sores will resolve on their own in about a week, Blumberg said.
But doctors usually recommend that patients take a prescription oral antiviral medication, such as acyclovir, valacyclovir or famciclovir. Antiviral medications are very effective, Blumberg said. And taking them as early as possible โ at the first sign of tingling or sensitivity around your mouth, for example โ can decrease the pain and shorten the time for healing, Johnston added. Sometimes, she said, it might prevent the bump from forming at all.
If you get six or more cold sores a year, your doctor may recommend something called suppressive antiviral therapy, which involves taking an antiviral medication every day to reduce the number, severity and length of outbreaks. This therapy may also reduce your chances of spreading the virus to others.
Many over-the-counter topical treatments โ such as those containing the active ingredient docosanol โ claim to heal cold sores quickly, sometimes in as few as two-and-a-half days. But the doctors we spoke with didnโt recommend them.
Topical medications are less effective than oral antiviral medications because they donโt penetrate into the nerve cells where the virus lives, so they canโt โaddress the root causeโ of outbreaks by stopping the herpes virus from replicating, said Dr Cindy Wassef, a dermatologist at the Robert Wood Johnson University Hospital in Somerset, New Jersey.
Topical medications also donโt heal the sores as quickly as oral antivirals, Johnston added.
But some over-the-counter products can help reduce pain while cold sores heal. These include steroid and numbing creams, Wassef said, and pain relievers like acetaminophen and aspirin, Blumberg added.
Itโs also helpful to avoid consuming anything acidic, like citrus or vinegar, which can make cold sores sting, Blumberg said. Cold drinks, ice pops and ice cream, on the other hand, can help soothe the pain.
Can you cure cold sores?
While individual cold sore episodes will heal, thereโs no way to banish the virus from your body, so youโll always be at risk for future outbreaks, Wassef said.
โHSV-1 is a chronic infection,โ Johnston added. โRight now, there is no cure.โ
However, if you know that your outbreaks are prompted by certain triggers, like exposure to ultraviolet light, for example, you could try avoiding that trigger, such as by wearing sunscreen or lip balm with an SPF of at least 30, Blumberg said.
Scientists have been working on a herpes vaccine, which Johnston said is still early in the research and testing phase. Most of the work has been done on genital herpes, more commonly caused by the herpes simplex virus type 2, she explained, but โhopefully, once we get a breakthrough there, we could then study it in cold soresโ.
Researchers are also looking into therapies that alter the DNA of the virus in your body. In a 2024 study, scientists injected mice with gene editing molecules. This removed 90% of the herpes virus involved in cold sores (and 97% of the virus involved in genital herpes). The authors concluded that gene editing could potentially contribute to a cure for oral and genital herpes, but more research is needed.
For now, the only way to prevent cold sores is to avoid contracting the herpes virus in the first place โ but thatโs practically impossible for many people, Johnston said. โItโs a very ubiquitous virus.โ
This article originally appeared in The New York Times.
Written by: Erica Sweeney
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