Cold sores—also known as fever blisters—are not caused by the common cold but they are related. They are caused by a different type of virus known as herpes. Show Typically, cold sores on the mouth are caused by herpes simplex 1 (HSV-1), while herpes simplex 2 (HSV-2) causes sores in the genital area. However, it is possible for either virus to cause sores in either area. belchonock / Getty ImagesOverviewNearly everyone has the HSV-1 virus inside their body by the time they reach 10 years old. Not everyone will experience symptoms though. If you are infected with HSV-1, the first time it makes you sick can be very different from the cold sores you experience after that. During first time infections, people may experience:
After the first infection, you may experience tingling or itching around the area a day or two before a cold sore appears. Then, the small blisters that are filled with fluid form somewhere around the edge of your lips. They may also appear around the nose or cheeks. The blister will then burst and ooze fluid until they crust over after a few days. The scabbed area should disappear within two weeks. If you carry HSV-1, you may experience cold sore "breakouts" throughout your life. They can be triggered by stress or illness, which may be why they got the name cold sores and fever blisters. Although they can develop during an illness such as a cold or the flu, cold sores are not actually caused by the cold or flu viruses. TreatmentMost cold sores do not require treatment. They will go away on their own within two weeks. If they do not, they occur very frequently or they appear in multiple places on the body, you should contact your healthcare provider. There are over-the-counter (OTC) treatments that may help with your symptoms. These include Abreva (docosanol), OTC remedies that contain a drying agent, and ice or cold compresses to relieve pain. If your healthcare provider decides that your symptoms are severe enough that you need prescription treatment, there are several antiviral medications they may prescribe. These include:
These may be available as a cream or pill, although the pills are generally more effective. If the infection is widespread and severe, it may require IV treatment and hospitalization. Alternative therapies may be used to try to treat cold sores as well. Although the efficacy of these treatments is unclear, there is some evidence that lemon balm (lip balm containing 1% lemon extract) may help shorten healing time and prevent a recurrence. Lysine has also been used as a supplement to help with cold sores. When to Be ConcernedIf your cold sore does not go away within two weeks, you should contact your healthcare provider. People with weakened immune systems are at higher risk for complications from cold sores than others. Other things to watch for and seek medical treatment for include:
PreventionIf your outbreaks are triggered by stress, using stress-reducing techniques such as deep breathing or meditation may help. You should avoid contact with others while blisters are present—especially kissing and sharing food or eating utensils. Be careful about touching other parts of your body when blisters are present as the virus can spread. This can be very dangerous, especially if it gets into the eyes. Wash your hands frequently. If you have a cold sore, be sure to wash your hands frequently to avoid spreading the virus to other people. If you get cold sores a lot, talk to your healthcare provider to see if taking an antiviral medication on a regular basis may help you. Frequently Asked Questions
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By Kristina Duda, RN Thanks for your feedback! Is a cold sore and fever blister the same thing?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.
What can trigger a fever blister?Causes. Fever Blisters are caused by an infection with the herpes simplex virus, usually type 1, or HSV-1. It is estimated that nearly 90 percent of U.S. adults have been infected with the virus, although many people with the infection do not ever show symptoms.
How do I get rid of a fever blister on my lip?A cold, damp cloth may reduce redness, help remove crusting and promote healing. Or try a warm compress to the blisters to ease pain. Rest and try pain relievers. Take over-the-counter pain relievers if you have a fever or the cold sore is painful.
Can you have a blister on your lip that isn't a cold sore?What causes lip blisters? Blisters on the lip include cold sores, sunburn blisters, and canker sores. A person should pay attention to the blister's location and its appearance to help identify the cause. There are many reasons why lip blisters develop, including infections, sun damage, and allergies.
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