Herpes Simplex Virus Empiric Therapy 

Although lesions caused by herpes simplex virus (HSV) subtypes HSV-1 and HSV-2 differ in rates of recurrence and subclinical shedding, they are treated with the same antiviral regimens, based on the site of infection. ^{[1, 2, 3, 4]}

Genital herpes

First episode

Treatment is recommended for all patients, as symptoms can be severe and/or prolonged. Continue treatment past 10 days if symptoms persist. ^{[1, 3, 4]} Regimens are as follows:

• Acyclovir 200 mg PO 5 times daily for 7-10 days or
• Acyclovir 400 mg PO TID for 7-10 days or
• Famciclovir 250 mg PO TID for 7-10 days or
• Valacyclovir 1000 mg PO BID for 7-10 days

Recurrent episodes

Initiate treatment during prodrome or within 24 hours of lesion appearance to ensure effectiveness. ^{[1, 3, 4]} Regimens are as follows:

• Acyclovir 400 mg PO TID for 5 days or
• Acyclovir 800 mg PO BID for 5 days or
• Acyclovir 800 mg PO TID for 2 days or
• Famciclovir 1000 mg PO BID for 1 day or
• Famciclovir 125 mg PO BID for 5 days or
• Famciclovir 500 mg PO once, followed by 250 mg PO BID for 2 days or
• Valacyclovir 500 mg PO BID for 3 days or
• Valacyclovir 1000 mg PO once daily for 5 days

Episodic infection in immunocompromised patients/those with HIV infection

Recommended regimens for episodic infection in immunocompromised patients/those with HIV infection ^[1] are as follows:

• Acyclovir 400 mg PO TID for 5-10 days or
• Famciclovir 500 mg PO BID for 5-10 days or
• Valacyclovir 1000 mg PO BID for 5-10 days

Suppressive therapy

Daily suppressive antiviral therapy reduces the rate of outbreaks and of subclinical shedding. Use of once-daily valacyclovir has been demonstrated to reduce the rate of transmission to HSV-2–seronegative partners. ^{[1, 3, 5, 4]}

• Acyclovir 400 mg PO BID or
• Famciclovir 250 mg PO BID or
• Valacyclovir 500 mg PO once daily (or 1000 mg PO once daily if ≥10 recurrences annually)

Recommended regimens for daily suppressive therapy in immunocompromised patients/those with HIV infection include the following: ^[1]

• Acyclovir 400-800 mg PO BID or TID or
• Famciclovir 500 mg PO BID or
• Valacyclovir 500 mg PO BID

Herpes labialis

Episodic therapy

Initiate treatment within 48 hours of symptom onset. ^{[3, 6, 7, 4, 8]} Regimens include the following:

• Acyclovir 400 mg PO 5 times daily for 5 days or
• Famciclovir 1500 mg PO as a single dose or
• Valacyclovir 2000 mg PO BID for 1 day or
• Docosanol Cream 10% (Abreva; available without prescription), applied topically 5 times daily until healed, for up to 10 days or
• Acyclovir cream 5%, applied topically 5 times a day for 4 days or
• Penciclovir cream 1%, applied topically every 2 hours while awake for 4 days

Suppressive therapy

Regimens include the following: ^{[3, 6, 4, 8]}

• Acyclovir 400 mg PO BID or
• Valacyclovir 500 mg PO once daily

Severe herpes simplex virus disease

Disseminated HSV disease or severe symptoms in the immunocompromised patient ^[1] : Acyclovir 5-10 mg/kg IV q8h for 2-7 days until clinical improvement is observed, followed by oral antiviral therapy, to complete at least 10 days total of therapy

HSV meningoencephalitis ^{[3, 9]} : Acyclovir 10-20 mg/kg IV q8h for 14-21 days

Neonatal HSV ^{[3, 9]} : Acyclovir 20 mg/kg IV q8h for 14-21 days

See Herpes Simplex Viruses: Test Your Knowledge, a Critical Images slideshow, for more information on clinical, histologic, and radiographic imaging findings in HSV-1 and HSV-2.