What is the prophysis (prophylaxis) of herpes simplex labialis (cold sores)?

From the Guidelines

Cold sore prophylaxis should be initiated with valacyclovir 500 mg daily, acyclovir 400 mg twice daily, or famciclovir 250 mg twice daily for patients with frequent recurrent attacks. These medications are recommended for suppressive therapy, especially for individuals experiencing more than 6 outbreaks per year 1. The goal of prophylaxis is to reduce the frequency and severity of herpes simplex virus (HSV-1) outbreaks, and oral antiviral medications have been shown to be effective in achieving this goal.

Key Considerations

• Patients should be asked if they have a history of HSV infection before commencing immunosuppressive therapy 1
• Routine prophylaxis to suppress virus replication should be considered for patients with frequent recurrent attacks, who are already taking intermittent suppressive antiviral therapy, or both 1
• Antivirals work by inhibiting viral DNA replication, preventing the virus from multiplying, and significantly reducing viral shedding and outbreak frequency
• Prophylactic therapy is generally well-tolerated with minimal side effects, though some patients may experience headache, nausea, or dizziness

Additional Measures

• Applying sunscreen (SPF 30+) to the lips when outdoors can help prevent recurrences
• Managing stress, avoiding sharing personal items during outbreaks, and maintaining good overall health can also help prevent recurrences
• For those with predictable triggers like sun exposure or menstruation, short-term prophylaxis can be initiated 24 hours before the trigger and continued for 5-7 days

Evidence-Based Recommendation

The most recent and highest quality study recommends valacyclovir 500 mg daily, acyclovir 400 mg twice daily, or famciclovir 250 mg twice daily for cold sore prophylaxis 1. This study provides the most up-to-date guidance on the prevention and management of herpes simplex virus infections, including cold sores.

From the FDA Drug Label

Patients should be advised to initiate treatment at the earliest symptom of a cold sore (e.g., tingling, itching, or burning). There are no data on the effectiveness of treatment initiated after the development of clinical signs of a cold sore (e.g., papule, vesicle, or ulcer). Patients should be instructed that treatment for cold sores should not exceed 1 day (2 doses) and that their doses should be taken about 12 hours apart.

The prophylaxis of herpes simplex labialis (cold sores) is not explicitly stated in the provided drug labels as a method of prevention. However, the labels do provide information on the treatment of cold sores.

• The treatment should be initiated at the earliest symptom of a cold sore.
• The treatment should not exceed 1 day (2 doses), with doses taken about 12 hours apart 2. Note that the provided information is about treatment, not prophylaxis.

From the Research

Prophylaxis of Herpes Simplex Labialis

The prophylaxis of herpes simplex labialis (cold sores) can be achieved through various methods, including:

• Oral Antiviral Agents: Long-term use of oral antiviral agents such as acyclovir 3, 4, 5 and valacyclovir 3, 4, 6, 5, 7 can prevent recurrent herpes labialis.
• Topical Antiviral Agents: Topical antiviral agents such as 5% acyclovir cream 3, 4, 5, 7 and 1% penciclovir cream 5, 7 can be used for episodic treatment, but are not effective in preventing recurrent herpes labialis.
• Sunscreen: Application of sunscreen with SPF 15 or above can prevent recurrent herpes labialis induced by ultraviolet light 3, 4.
• Other Interventions: Other interventions such as thymopentin, low-level laser therapy, and hypnotherapy have limited evidence for their effectiveness in preventing recurrent herpes labialis 4.

Prevention Strategies

Prevention strategies for herpes simplex labialis include:

• Daily Oral Antiviral Therapy: Daily oral antiviral therapy with acyclovir or valacyclovir can reduce the frequency and severity of recurrences 5, 7.
• Chronic Suppressive Therapy: Chronic suppressive therapy with oral antiviral agents should be considered for patients with severe or frequent recurrences 7.
• Prompt Treatment: Prompt treatment with oral antiviral agents during the prodromal stage or within 48 hours of lesion onset can shorten the duration of pain and discomfort, hasten healing, and reduce viral shedding 7.