Cold Sores: Causes, Symptoms, Treatment, Complications, Prevention


Cold sores are caused by the herpes simplex virus type 1 (HSV-1). HSV-1 is a very common virus, and most people are exposed to it at some point in their lives. However, not everyone who is exposed to HSV-1 will develop cold sores.


The first time you are infected with HSV-1, you may develop a primary infection. Symptoms of a primary infection can include:

  • Fever
  • Blisters in the mouth or on the genitals
  • Swollen glands
  • Muscle aches
  • Headache

After the primary infection, the virus remains dormant in your body. However, it can be triggered to reactivate, causing cold sores. Cold sores typically appear on the lips or around the mouth, but they can also appear on the nose or cheeks.

The first sign of a cold sore is often a tingling or burning sensation in the area where the sore will develop. Within a few days, a blister will form. The blister will eventually break open and form a scab. The scab will fall off after about 7-10 days.


There is no cure for cold sores, but there are treatments that can help to shorten the duration of the outbreak and relieve symptoms. Over-the-counter pain relievers, such as ibuprofen or acetaminophen, can help to reduce pain and inflammation. Antiviral creams, such as docosanol or penciclovir, can help to shorten the duration of the outbreak. Prescription antiviral medications, such as valacyclovir and famciclovir, can also be used to treat cold sores.


Cold sores are usually not a serious condition, but they can lead to complications in some people. These complications can include:

  • Infection: Cold sores can become infected with bacteria, which can lead to redness, swelling, and pain.
  • Eczema herpeticum: This is a severe skin infection that can occur in people with eczema.
  • Herpetic keratitis: This is an infection of the cornea that can lead to blindness.
  • Neonatal herpes: This is a serious infection that can occur in babies born to mothers with herpes.


There is no surefire way to prevent cold sores, but there are some things you can do to reduce your risk, such as:

  • Avoid contact with people who have cold sores.
  • Wash your hands frequently with soap and water.
  • Avoid touching your eyes, nose, and mouth.
  • Avoid stress, as stress can trigger cold sores.
  • Get enough sleep.
  • Eat a healthy diet.

If you have cold sores, there are some things you can do to prevent the spread of the virus, such as:

  • Avoid kissing or sexual contact until the cold sores are completely healed.
  • Cover the cold sores with a bandage.
  • Wash your hands frequently with soap and water.

If you have any questions or concerns about cold sores, talk to your doctor.