Cold Sores Fever Blisters

Overview, Causes, & Risk Factors

Fever blisters are small sores in the mouth or the area around it. They usually develop on the gums, roof of the mouth, outside of the lips, or the nostrils.

What is going on in the body?

Fever blisters are caused by the two types of herpes simplex virus. Most fever blisters are caused by herpes simplex virus 1, or HSV 1, which causes oral herpes. The virus that causes genital herpes, HSV 2, may also cause fever blisters.

The two stages of oral herpes are primary infection and recurrenceof infection. At some time during childhood, most people come down with theprimary infection. The individual may or may not have symptoms. This primary infection takesabout 2 weeks to clear up. After that, the virus remains in the body but is inactive.

After this primary infection, there can be a recurrence at any time. Many outbreaks occur without any obvious reason. However, the following factors may trigger a recurrence:

  • dental work
  • emotional stress
  • exposure to sunlight
  • fatigue
  • an upper respiratory infection, such as a cold or flu
  • What are the causes and risks of the condition?

    Fever blisters are caused by a herpes virus. People in the following categories may be more at risk for oral herpes:

  • people undergoing radiation therapy or chemotherapy
  • people with cancer or other debilitating diseases
  • people with HIV or other immunodeficiency disorders
  • Symptoms & Signs

    What are the signs and symptoms of the condition?

    Someone with an active oral herpes infection may have the following symptoms:

  • difficulty eating
  • fatigue
  • fever
  • malaise, or a vague feeling of illness
  • sore throat
  • swelling and redness, usually both before and during an outbreak
  • tiny blisters that grow into larger sores in the mouth, on the tongue,or on the lips
  • Diagnosis & Tests

    How is the condition diagnosed?

    Herpes is generally diagnosed with a medical history and physical exam. There arelaboratory tests for this virus, but they are seldom needed.

    Prevention & Expectations

    What can be done to prevent the condition?

    The virus that causes fever blisters can be passed from person to person. Someone with oral herpes should not share lipstick, utensils, or drinks with others. Touching and kissing can also spread the virus.

    What are the long-term effects of the condition?

    Fever blisters cause no serious long-term effects. The virus will stay in the person’s body indefinitely.

    What are the risks to others?

    The herpes virus can be spread from person to person much like acold or flu. Sores also can be spread to other parts of the body such as fingers or eyes. Sometimes sores can also spread to the genitals.

    Treatment & Monitoring

    What are the treatments for the condition?

    In most cases, fever blisters are self-limiting. They willusually crust over and go away in about 2 weeks. If they last longer, the healthcare professional should be consulted. Treatment for oral herpes includes the following:

  • diluted, or 1 1/2%, hydrogen peroxide mouthrinse
  • lip balm to soothe sores on the lips
  • penciclovir cream
  • prescription antiviral medicines, such as acyclovir,valacyclovir, and famciclovir
  • salt-water rinse, with 1/2 teaspoon salt in 8 ounces of warm water
  • sunblock cream for lip protection
  • What are the side effects of the treatments?

    Antiviral medications may cause nausea, vomiting, diarrhea, and allergic reactions. Creams and ointments may cause an allergic reaction in some individuals.

    What happens after treatment for the disease?

    The sores usually clear up and go away in about 2 weeks. Ifthey last longer than this or if they come back often, the healthcare provider should beconsulted.

    How is the condition monitored?

    Any new or worsening symptoms should be reported to the healthcare provider.

    Article type: xmedgeneral