What is the recommended treatment for a patient experiencing a Herpes Simplex Virus (HSV) flare-up?

Treatment for HSV Flare-Up

For an acute HSV flare-up, initiate valacyclovir 500 mg orally twice daily for 5 days, starting immediately at the first sign of prodromal symptoms or within 24 hours of lesion onset for maximum effectiveness. 1, 2

Episodic Treatment Regimens

First-line options for treating an active HSV recurrence include:

• Valacyclovir 500 mg orally twice daily for 5 days is the preferred regimen due to convenient twice-daily dosing and proven efficacy 1, 2
• Acyclovir 400 mg orally three times daily for 5 days 1, 2
• Acyclovir 800 mg orally twice daily for 5 days 1, 2
• Acyclovir 200 mg orally five times daily for 5 days 1, 2
• Famciclovir 125 mg orally twice daily for 5 days 1, 2

Critical Timing for Treatment Success

Treatment must be initiated during the prodromal period (tingling, itching, burning) or within 24 hours of lesion onset to achieve maximum benefit 1, 2, 3

• Delaying treatment beyond 72 hours significantly reduces effectiveness 4, 2
• Treatment initiated more than 2 days after lesion onset provides minimal benefit in immunocompetent patients 2
• Patients should be provided with a prescription to self-initiate treatment at the first sign of recurrence, rather than waiting for a clinic visit 4, 2

When to Consider Suppressive Therapy Instead

Daily suppressive therapy should be considered for patients experiencing ≥6 recurrences per year 4, 1

Suppressive regimens include:

• Valacyclovir 500 mg orally once daily (preferred for convenience) 4, 1
• Valacyclovir 1 g orally once daily 4, 1
• Acyclovir 400 mg orally twice daily 4, 1
• Famciclovir 250 mg orally twice daily 4, 1

Suppressive therapy reduces recurrence frequency by at least 75% and decreases asymptomatic viral shedding 4, 1

• After 1 year of continuous suppressive therapy, discontinue treatment to reassess recurrence frequency 4, 1
• Suppressive therapy has documented safety for up to 6 years with acyclovir and 1 year with valacyclovir 4

Management of Acyclovir-Resistant HSV

If lesions do not begin to resolve within 7-10 days of standard antiviral therapy, suspect acyclovir resistance 1

• Foscarnet 40 mg/kg IV every 8 hours is the treatment of choice for proven or suspected acyclovir-resistant HSV 1, 5
• This scenario occurs primarily in immunocompromised patients 5, 6

Critical Pitfalls to Avoid

• Never use topical acyclovir alone, as it is substantially less effective than oral systemic therapy 4, 1, 2
• Do not withhold episodic treatment prescriptions even if the patient is not on suppressive therapy—early self-initiated treatment is crucial 4, 2
• Avoid valacyclovir 8 g per day in immunocompromised patients, as this dose is associated with hemolytic uremic syndrome/thrombotic thrombocytopenic purpura 1
• Do not initiate suppressive therapy in patients with infrequent recurrences (fewer than 6 per year), as the benefit does not justify continuous medication 4, 2

Essential Patient Counseling

All patients with HSV should receive comprehensive counseling regardless of treatment approach 4, 1, 2:

• HSV is a chronic, incurable viral infection with potential for recurrence; antiviral medications control symptoms but do not eradicate the virus 1, 2, 3
• Abstain from sexual activity when lesions or prodromal symptoms are present 1, 2
• Use condoms during all sexual exposures, as asymptomatic viral shedding can occur even without visible lesions 4, 1, 2
• Inform sex partners about having genital herpes, as they may be infected even if asymptomatic 1, 3
• Women of childbearing age should inform prenatal care providers about their genital herpes history due to risk of neonatal infection 4, 2