Treatment for Acute Herpes Simplex Virus (HSV) Outbreak
For acute HSV outbreaks, acyclovir 800 mg orally 5 times daily for 7-10 days is the first-line treatment with the most extensive clinical experience. 1
First-Line Antiviral Options
- Acyclovir: 800 mg orally 5 times daily for 7-10 days
- Valacyclovir: 1000 mg orally 3 times daily for 7-10 days
- Famciclovir: 500 mg orally 3 times daily for 7-10 days
These medications are most effective when started within 72 hours of symptom onset, though some benefit may still be obtained when starting treatment later, especially in patients with continued new lesion formation 1.
Dosage Considerations
Renal Adjustment for Acyclovir
| Creatinine Clearance (mL/min) | Dose 800 mg |
|---|---|
| >25 | 800 mg every 4 hours, 5 times a day |
| 10-25 | 800 mg every 8 hours |
| 0-10 | 800 mg every 12 hours |
Special Populations
- Children <45 kg: Acyclovir 20 mg/kg (maximum 800 mg/dose) orally 4 times daily for 7-10 days 1
- Immunocompromised patients: May require higher doses and longer treatment duration
- Pregnant women: Acyclovir 800 mg orally 5 times daily is considered safe 1
Treatment for Severe or Resistant Cases
- Severe cases: Intravenous acyclovir 10 mg/kg every 8 hours 1
- Acyclovir-resistant infections: Foscarnet 40 mg/kg IV 3 times daily 1, 2
- For accessible lesions with resistance: Topical trifluridine (TFT) applied 3-4 times daily until complete healing 3
Pain Management for HSV Outbreaks
For associated pain and discomfort:
- Mild pain: Acetaminophen or NSAIDs
- Moderate to severe pain: Consider gabapentin, pregabalin, or tricyclic antidepressants 1
- Localized pain: Lidocaine patches or topical anesthetics 1
- Oral lesions: Viscous lidocaine 2% mouthwash or sodium bicarbonate mouthwash (non-alcoholic) hourly 1
Alternative Short-Course Regimens
Recent studies have shown effectiveness with shorter treatment courses, which may improve patient compliance:
- 2-day regimen: Acyclovir 800 mg orally 3 times daily for 2 days has been shown to significantly reduce the duration of lesions, episodes, and viral shedding 4
- Single-day regimen: Famciclovir 1500 mg single dose for herpes labialis 5
Follow-Up and Monitoring
- Schedule follow-up within 7 days to assess treatment response
- Continue treatment until complete resolution of all lesions
- Monitor for signs of dissemination or complications 1
Common Pitfalls to Avoid
- Delayed treatment: Initiating therapy beyond 72 hours significantly reduces effectiveness
- Inadequate dosing: Underdosing can lead to treatment failure and potential resistance
- Failure to adjust for renal function: Can lead to toxicity in patients with impaired renal function
- Missing resistant infections: Consider resistance if lesions don't improve after 5-7 days of appropriate therapy
- Overlooking immunocompromised status: These patients require more aggressive treatment and monitoring
Suppressive Therapy for Frequent Recurrences
For patients with frequent recurrences (≥6 episodes per year), suppressive therapy may be considered: