Inpatient Treatment of Oral Herpes Simplex Virus (HSV) Sores

First-Line Treatment

The Centers for Disease Control and Prevention recommends intravenous acyclovir as the first-line therapy for severe mucocutaneous HSV lesions in the inpatient setting, due to its proven efficacy in treating severe mucocutaneous HSV lesions 1
Therapy with intravenous acyclovir should be continued until lesions have begun to regress, then transition to oral therapy, and complete treatment should continue until lesions have completely healed 1

The Centers for Disease Control and Prevention recommends oral regimens of acyclovir 400 mg orally three times a day for 7-10 days, or acyclovir 200 mg orally five times a day for 7-10 days, or famciclovir 250 mg orally three times a day for 7-10 days, or valacyclovir 1 g orally twice a day for 7-10 days for less severe cases or after initial IV treatment 2, 3
Higher dosages of acyclovir (400 mg orally five times a day) may be used in treatment studies of first-episode oral infection, including stomatitis or pharyngitis, and treatment may be extended if healing is incomplete after 10 days of therapy 2

The Centers for Disease Control and Prevention recommends initial treatment with IV acyclovir for immunocompromised patients with oral HSV lesions, and short-course therapy should not be used in patients with HIV infection 1
Treatment should be continued until complete healing of lesions in immunocompromised patients 1

If lesions do not begin to resolve within 7-10 days of therapy, suspect drug resistance, and obtain viral culture of the lesion and perform susceptibility testing 1
For confirmed acyclovir-resistant HSV, IV foscarnet is the treatment of choice 1

For patients on IV acyclovir, monitor renal function at initiation of treatment and once or twice weekly, and dose adjustment is necessary for patients with renal impairment 1
No routine laboratory monitoring is needed for patients on oral therapy unless they have substantial renal impairment 1

Topical acyclovir is substantially less effective than systemic therapy and should not be used as monotherapy for severe oral HSV lesions 1, 2
Delayed treatment reduces efficacy, and therapy should be initiated as soon as possible, and immunocompromised patients may develop resistance more frequently 4, 5
Patients with HIV may experience atypical and recalcitrant lesions, particularly during immune reconstitution inflammatory syndrome (IRIS) 1