Almost everyone knows what a cold sore is. However, many people are unaware what causes cold sores to develop. Cold sores are caused by the herpes simplex virus (HSV). The HSV virus has two different types – HSV-1 and HSV-2 – although most cold sores are caused by HSV-1.

HSV-1 is contagious, and many people contract it without knowing it. Cold sores can be transmitted from one person to another through kissing, sharing silverware, sharing food and drinks, close contact/touching during an outbreak, etc.

Once a person is infected with HSV-1, the virus remains in their body for life, remaining dormant until a trigger activates it, causing a cold sore to form.1 Common cold sore triggers include:

  • Exposure to UV radiation
  • Stress
  • Lack of sleep
  • Improper diet
  • Impaired immune system
  • Hormonal changes

Is There a Cure for Cold Sores?

Cold sores currently don’t have a known cure. However, you can help minimize your chances of suffering from a cold sore outbreak by knowing your triggers and acting quickly when you feel a cold sore forming.

Additionally, you may want to talk to your physician about prescription cold sore treatments. Your physician may recommend Sitavig® (acyclovir), 50mg Muco-Adhesive Buccal Tablet. Sitavig is a single-dose prescription cold sore treatment that can ease cold sore symptoms, speed up healing, and in some cases, stop cold sores before they start.


1- EMedicine Health (August 13, 2015). Cold Sores — Cold Sore Overview [Glossary]. Retrieved August 15, 2015, from


Sitavig should not be used in patients with known hypersensitivity to acyclovir, milk protein concentrate, or other components of the product.

Sitavig has not been studied in pregnant women or in immunocompromised patients and no interaction studies have been performed. Sitavig’s safety and efficacy have not been established in pediatric patients.

Sitavig is a Pregnancy Category B product; therefore it should be used during pregnancy only if the potential benefit outweighs the potential risk to the fetus. It is not known if Sitavig is excreted in breast milk; however, systemic absorption is minimal.

In a controlled clinical trial Sitavig’s most common side effects (greater than or equal to 1%) were: headache (3%), dizziness (1%), lethargy (1%), gingival pain (1%), aphthous stomatitis (1%), application site pain (1%), application site irritation (1%), erythema (1%) and rash (1%). In the same trial these side effects ranged from 0%-3% for placebo.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088.

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