What is the recommended treatment and dosage for a patient with Herpes Simplex Virus (HSV) lip bumps?

Treatment of HSV Lip Bumps (Herpes Labialis)

For HSV lip bumps (herpes labialis), start oral valacyclovir 1 gram twice daily for 1 day or famciclovir 1500 mg as a single dose, initiated within 48 hours of lesion onset for optimal efficacy. 1, 2, 3

First-Line Oral Antiviral Therapy

Oral antivirals are superior to topical therapy and should be the standard treatment approach. 1, 3, 4

Preferred Regimens (in order of convenience):

• Famciclovir 1500 mg as a single dose - FDA-approved for herpes labialis, offering the most convenient dosing 2, 3
• Valacyclovir 1 gram twice daily for 1 day - highly effective with minimal dosing burden 5, 3
• Acyclovir 400 mg orally three times daily for 5 days - less convenient but effective alternative 1, 5

Critical Timing Considerations:

• Treatment must begin within 48 hours of lesion onset (ideally during prodrome) to achieve meaningful reduction in healing time, pain duration, and viral shedding 3, 4
• Starting treatment after 48 hours provides minimal clinical benefit for herpes labialis 3
• Patients should be counseled to keep medication on hand and initiate at first sign of prodrome (tingling, burning) 3, 4

Topical Therapy (Inferior Alternative)

Topical antivirals are substantially less effective than oral therapy and should only be considered if oral therapy is refused or contraindicated. 1, 6

If topical therapy is used despite limitations:

• Penciclovir 1% cream applied every 2 hours while awake 3
• Acyclovir 5% cream applied 5 times daily 3
• These provide modest benefit but do not prevent recurrences 3

Special Populations

Severe or Moderate-to-Severe Gingivostomatitis:

• Acyclovir 5-10 mg/kg IV three times daily until lesions begin to regress, then switch to oral acyclovir 20 mg/kg (max 400 mg) three times daily until complete healing 1

Mild Gingivostomatitis:

• Acyclovir 20 mg/kg (max 400 mg) orally three times daily for 5-10 days 1

Immunocompromised Patients:

• Consider higher doses: acyclovir 400 mg orally 3-5 times daily until clinical resolution 6
• If severe or disseminated: acyclovir 10 mg/kg IV every 8 hours 6
• Monitor for acyclovir resistance if lesions persist beyond 7-10 days 6

Pediatric Patients:

• Acyclovir 20 mg/kg (max 400 mg) per dose orally three times daily for 5-10 days for children <45 kg 1
• Valacyclovir and famciclovir lack pediatric formulations and dosing data 1

Chronic Suppressive Therapy

For patients with ≥6 episodes per year, initiate daily suppressive therapy to reduce recurrence frequency by ≥75%. 5, 3

Suppressive regimens:

• Valacyclovir 500 mg orally once daily 5
• Acyclovir 400 mg orally twice daily 5
• Famciclovir 250 mg orally twice daily 5

These regimens are safe for extended use (up to 6 years documented with acyclovir) and should be reassessed annually 5

Acyclovir-Resistant HSV

For proven or suspected acyclovir resistance (lesions not improving after 7-10 days of therapy), switch to foscarnet 40 mg/kg IV every 8 hours. 1, 5

Key Clinical Pitfalls to Avoid

• Never rely on topical antivirals as primary therapy - they are substantially less effective than oral agents 1, 6, 3
• Do not use acyclovir 400 mg three times daily for shingles - this dose is only appropriate for HSV, not varicella-zoster virus 6
• Avoid delayed treatment initiation - efficacy drops dramatically after 48 hours from lesion onset 3, 4
• Do not prescribe valacyclovir 8 grams per day - associated with hemolytic uremic syndrome/thrombotic thrombocytopenic purpura in immunocompromised patients 5

Supportive Care for Lip Lesions

• Apply white soft paraffin ointment to lips every 2 hours to prevent drying and cracking 1
• Consider benzydamine hydrochloride spray every 3 hours for pain control 1
• Maintain good oral hygiene with warm saline rinses 1

Patient Counseling Points

• Antiviral medications do not eradicate latent virus or prevent all future recurrences 6, 5
• Lesions remain contagious until completely crusted - avoid contact with others, especially immunocompromised individuals and infants 6
• Asymptomatic viral shedding can occur, potentially leading to transmission 5
• Keep medication readily available to initiate at first sign of prodrome 3, 4