Cold Sores (Herpes Simplex I / HSV1)

Cold Sores

What Causes Cold Sores?

Cold sores are caused by a virus known as herpes simplex one, or HSV-1. When a person is first infected with the cold sore virus, it may cause no symptoms at all. This initial infection usually happens during childhood. The infection could cause a slight fever or generalized feeling of illness. In some cases, a red, swollen, blister-type sore develops on the skin around the mouth. This blister turns into an ulcer and then heals. Once the infection has healed, the cold sore virus travels along the nerve endings in the head and neck and becomes dormant within the nerve. The virus can reactivate later, frequently in response to a “trigger.”


Who Suffers From Cold Sores?

About 80 percent of all American adults carry the cold sore virus. For reasons that are not understood, only about 20 petcent suffer from recurring cold sores. It is not clear why the virus only becomes active again in certain people, or why most people who suffer the initial cold sore virus infection do not develop recurrent cold sores. Most cold sore sufferers experience one to three out´┐Żbreaks a year.

A Common Problem

Cold sores are a common problem. Close to 50 million people in the United States suffer at least one outbreak each year. Many cold sore sufferers do not consider a cold sore as a serious problem. However, during an outbreak, cold sore sufferers experience discomfort or pain, and may avoid going out in public. Cold sores can cause social embarrassment. And although it is true that an infection with the HSV-1 virus is not usually serious, it can be serious in people with weakened immune systems. These people include cancer patients, organ transplant patients, or those with HIV/AIDS.

Why Do Cold Sores Occur?

Even when a cold sore is healed the virus remains in your body – it becomes dormant, hidden away from your immune system. A new outbreak occurs when the dormant virus becomes active again. Cold sores often recur at the site near where the last one occurred. The active virus invades healthy lip cells by fusing with the cell’s membrane, and begins to reproduce. The virus needs to invade the cell to reproduce. If the cold sore is not treated, the virus will keep invading healthy cells in the area, leading to more and more cells infected; until your immune system responds and fights the virus back into remission.

Stages of a Cold Sore Outbreak

Most people who suffet from recurrent cold sores recognize the distinct stages of a cold sore infection. The first stage, or prodrome, begins with a tingling sensation, a feeling of skin tightening in the area where the cold sore is about to develop. Some people describe an itching or burning sensation. As the cold sore develops, you know you are in the second stage when a red (usually painful) bump develops. This stage lasts from hours to a day or two. During the third stage, tiny fluid-filled blisters form, and may combine to form one larger blister. These blisters are often painful and last about a day. The fourth stage is usually the most painful and serious, during which the blisters rupture, forming an ulcer. During this stage, the cold sore is most contagious. Finally, during the last stages, the ulcer becomes covered with a soft crust which hardens into a dry scab (which can bleed). Patients often complain of itching and burning during this stage, which can last up to three days. During a final healing stage of another 3 or 4 days, a series of scabs form and flake off. Eventually the skin appears normal again. The entire outbreak lasts for 7 to 1 0 days if it is not treated.

Treatment Goals

There is no cure for recurring cold sores. The primary goal of cold sore treatment is to speed healing and shorten the duration of symptoms. There are currently four prescription medications and one over-the-counter medication that have been proven effective in reaching this treatment goal.

Products Used in the Treatment of Cold Sores

There are four prescription medications specifically approved by the FDA for the treatment of cold sores. These include oral Valtrex (valacyclovir), oral Famvir (famciclovir), Zovirax (acyclovir) 5% cream, and Denavir (pencyclovir) 1% cream. These medications work by stopping the cold sore virus from reproducing within your cells. They are used in patients who have frequent cold sores that do not respond to other treatment. They are also used to treat cold sore outbreaks in patients who could develop serious complications from the HSV-1 viral infection.

Abreva (10 % docosanol cream) is the only nonprescription treatment for cold sores that is approved by the FDA to actually shorten the duration of symptoms and speed healing. It works by strengthening the cell membrane of the healthy cells around those invaded by the virus. The stronger cell membrane helps prevent the virus from entering and infecting more cells. Abreva works best if used during the earliest stage of a cold sore outbreak (sometimes called the “tingle” stage). It is available in a tube, or in a new pump that dispenses a single dose at a time. Abreva should be applied 5 times a day to the affected area until the cold sore has healed.

Products that Provide Symptomatic Relief

Several over-the-counter cold sore products are available that are formulated to soothe symptoms of a cold sore outbreak. Studies with these products have not been accepted by the FDA as proof that they shorten symptom duration or speed healing. Many of these nonprescription products contain moisturizers or moisture barriers, which can help prevent dryness and cracking as cold sores heal. Products that contain local anesthetics such as tetracaine can help control pain. Some symptom-relief products include menthol, camphor or phenol to stop itching. The addition of sunscreens to symptomatic relief products allows protection from the sun, thought to be a common trigger of outbreaks. Zinc oxide and the amino acid L-lysine are also found in some formulations. These ingredients may have some antiviral activity, although their effectiveness has not been proven in scientific studies. Ingredients that are not recommended for symptom relief include antiseptic or disinfectant products such as alcohol or hydrogen peroxide, since they can cause dryness and irritation. Products containing corticosteroids are also not recommended since they suppress the normal immune response, which can delay healing.

Prevention Tips

To prevent cold sore outbreaks, try to avoid the triggers that activate the cold sore virus. Use a lip moisturizer with sunscreen regularly and avoid the sun and sun lamps. Stay healthy by eating a balanced diet, getting a good night’s sleep, and relaxing during stressful periods. These steps will help keep the body’s immunity strong. Using nonprescription Abreva at the first sign of an outbreak is even easier with the availability of a new pump dispenser.

Self-treatment of cold sores with an over-the-counter medication is fine if you have had cold sores before and you have a normal immune system. Most cold sore sufferers can treat their cold sores without seeing a doctor. If the ulcer becomes infected or lasts more than 10 days, see your doctor. If you have questions about medications used to treat cold sores, or products designed to relieve the symptoms of cold sores, be sure to ask your pharmacist.
US Pharmacist
Copyright 2003 Jobson Publishing, LLC