Cold Sore Blister – Basic Information About Herpes Simplex, Treatments, and Simple First Aid


What Is A Cold Sore Blister?

A cold sore blister is the external symptom of an active outbreak of the herpes simplex virus (HSV), most likely the type 1 strain (aka “HSV-1”), although both the type 1 and type 2 strains can cause both genital and oral herpes. Most genital herpes is caused by HSV-2, although HSV-1 accounts for about half of new cases in developed countries such as the U.S.

Active outbreaks are often preceded by what’s known as “prodrome” or “prodromal symptoms”, the most common of which is “paresthesia”–the tingling or prickly sensation at the site of the oncoming cold sore before it actually shows up. This is actually a very reliable indicator that a cold sore is imminent and any preventative measures you can take should be taken at this point (anti-virals, OTC creams, ice, etc.). If you have a prescription from your doctor for anti-viral medications such as acyclovir or valcyclovir, you should begin taking them as soon as prodromal symptoms begin–the sooner you start the more effective they will be and the shorter and less painful your outbreak will be.

How Often Will I Get Cold Sores and Can I Ever Get Rid of Them?

HSV cycles between periods of active outbreaks that last between 2 and 21 days where there are blisters on the skin containing infectious virus, then followed by a remission period–this is the state the virus is in almost all the time. During remission the virus stays contained completely inside the sensory nerve cells in its latent form where it will remain for the rest of the your life. Over time the frequency of active disease lessens. So no, sorry, there’s no cure for cold sores, although there are several vaccines currenly in Phase III trials, such as Herpevac and Zostavax, that have shown very promising potential in dealing with the herpes simplex virus.

Treatments For Cold Sore Blisters

There are three main prescription treatments available that are prescribed for cold sore sufferers, they will all roughly produce the same result of reducing healing time by 1-2 days and decreasing the pain and irritation of the cold sore(s):

Acyclovir: Acyclovir was the original, and prototypical, member of this drug class; it is now available in generic brands at a greatly reduced cost. Acyclovir is the recommended antiviral for suppressive therapy for use during the last months of pregnancy to prevent transmission of herpes simplex to the neonate in cases of maternal recurrent herpes.
Valacyclovir: Valacyclovir was approved by the FDA specifically to reduce cold sore duration in people who are at least 12 years of age or older, and it’s also been noted that Valacyclovir is absorbed much easier than other anti-viral medications such as Acyclovir. Valacyclovir and famcyclovir-prodrugs of acyclovir and pencyclovir, respectively-have improved solubility in water and better bioavailability when taken orally. Possible side effects include allergic reaction, headache, skin rash, insomnia, dizziness, and fatigue.
Famciclovir: This medication is sometimes used to treat the herpes virus that causes cold sores as well as genital herpes (it acts on both the HSV-1 and HSV-2 strains, in other words), and studies have shown that it can work as well as Acyclovir in treating oral herpes outbreaks. Possible side effects include itching, fever, headache, fatigue, nausea, or diarrhea. Several studies in humans and mice provide evidence that early treatment with famciclovir soon after the first infection with herpes can significantly lower the chance of future outbreaks of herpes (Source: Journal of General Virology–See: )

Cold Sore First Aid Basics

1. Do not itch or scratch! This can cause you to spread the virus to other areas of the body, particularly the eyes which can be very dangerous–herpes keratitis (herpes infection of the eye) is a leading cause of blindness in the United States.

2. Start applying ice–I’d recommend 10 minutes every 2 hours. Just apply an ice cube directly to the affected area, this will reduce inflammation and slow the replication of the virus. It also reduces irritation and itching.

3. Start anti-virals if you’ve got them, see your doctor for them if you don’t and would like to try anti-viral therapy.

4. Keep the area clean and dry by washing it with a clean, new washcloth every couple of hours; just use normal soap and water.

5. Apply a benzoyl peroxide based acne cream such as Clearasil to keep it dry until you wash it again.