Learn more about the causes, symptoms, treatment and prevention of this common lip sore caused by the herpes simplex virus type 1 (HSV-1).
Cold sores — also called fever blisters — are a common viral infection. They are tiny, fluid-filled blisters on and around your lips. These blisters are often grouped together in patches. After the blisters break, a scab forms that can last several days. Cold sores usually heal in two to three weeks without leaving a scar.
Cold sores spread from person to person by close contact, such as kissing. They're usually caused by herpes simplex virus type 1 (HSV-1), and less commonly herpes simplex virus type 2 (HSV-2). Both of these viruses can affect your mouth or genitals and can be spread by oral sex. Cold sores are contagious even if you don't see the sores.
There's no cure for cold sores, but treatment can help manage outbreaks. Prescription antiviral pills or creams can help sores heal more quickly. And they may reduce the frequency, length and severity of future outbreaks.
A cold sore usually passes through several stages:
Signs and symptoms vary, depending on whether this is your first outbreak or a recurrence. The first time you have a cold sore, symptoms may not start for up to 20 days after you were first exposed to the virus. The sores can last several days, and the blisters can take two to three weeks to heal completely. Recurrences typically appear at the same spot each time and tend to be less severe than the first outbreak.
In a first-time outbreak, you also might experience:
Children under 5 years old may have cold sores inside their mouths and the lesions are commonly mistaken for canker sores. Canker sores involve only the mucous membrane and aren't caused by the herpes simplex virus.
Cold sores generally clear up without treatment. See your doctor if:
Cold sores are caused by certain strains of the herpes simplex virus (HSV). HSV-1 usually causes cold sores. HSV-2 is usually responsible for genital herpes. But either type can spread to the face or genitals through close contact, such as kissing or oral sex. Shared eating utensils, razors and towels might also spread HSV-1.
Cold sores are most contagious when you have oozing blisters because the virus easily spreads through contact with infected body fluids. But you can spread the virus even if you don't have blisters. Many people who are infected with the virus that causes cold sores never develop signs and symptoms.
Once you've had an episode of herpes infection, the virus lies dormant in nerve cells in your skin and may emerge as another cold sore at the same place as before. Recurrence may be triggered by:
Almost everyone is at risk of cold sores. Most adults carry the virus that causes cold sores, even if they've never had symptoms.
You're most at risk of complications from the virus if you have a weakened immune system from conditions and treatments such as:
In some people, the virus that causes cold sores can cause problems in other areas of the body, including:
Your doctor may prescribe an antiviral medication for you to take on a regular basis if you develop cold sores more than nine times a year or if you're at high risk of serious complications. If sunlight seems to trigger your recurrences, apply sunblock to the spot where the cold sore tends to erupt. Or talk with your doctor about using an oral antiviral drug as a preventive if you expect to be doing an activity that tends to trigger your condition, such as intense sunlight exposure.
To help avoid spreading cold sores to other people or to other parts of your body, you might try some of the following precautions:
Your doctor can usually diagnose cold sores just by looking at them. To confirm the diagnosis, your doctor might take a sample from the blister for testing in a laboratory.
Cold sores generally clear up without treatment in two to four weeks. Several types of prescription antiviral medications may speed the healing process. Examples include:
Some of these products are packaged as pills to be swallowed. Others are creams to be applied to the sores several times a day. In general, the pills work better than the creams. For very severe infections, some antiviral drugs can be given with an injection.
The over-the-counter cold sore ointment docosanol (Abreva) may shorten the healing time of a cold sore. At the first sign of symptoms, apply it to the affected skin as directed on the package. Use a cotton-tipped swab to put medicine on a cold sore. This helps prevent the spread of the sores to other parts of your body.
To ease the discomfort of a cold sore:
Although study results have been mixed, alternative medicine treatments for cold sores include:
Cold sores generally clear up without treatment in two to four weeks. Make an appointment with your family doctor if your cold sores:
Before your appointment, you may want to list answers to the following questions:
Below are some basic questions to ask your doctor about cold sores.
Your doctor is likely to ask you a number of questions. Being ready to answer them may reserve time to go over any points you want to talk about in-depth. Your doctor may ask:
June 17th, 2020