Treatment of Herpes Simplex Virus (HSV) in the Nose in Immunocompromised Patients
For an immunocompromised patient with herpes in the nose (mucocutaneous HSV), valacyclovir should be given at 1 gram orally twice daily, continuing treatment for 7-10 days and until all lesions have completely healed—which may require extending therapy beyond 10 days if lesions persist. 1
Initial Assessment and Treatment Decision
The critical first step is determining disease severity:
- Localized mucocutaneous HSV (limited to nasal area without dissemination): Oral valacyclovir is appropriate 1
- Severe, disseminated, or visceral HSV: Requires immediate escalation to IV acyclovir 5-10 mg/kg every 8 hours 1
- Acyclovir-resistant HSV (suspected if lesions fail to improve after 7-10 days): Switch to IV foscarnet 40 mg/kg every 8 hours 1, 2
Dosing Regimen for Localized Disease
For immunocompromised patients with localized mucocutaneous HSV:
- Valacyclovir 1 gram orally twice daily is the preferred first-line regimen 1
- This dosing provides superior bioavailability compared to standard acyclovir and requires less frequent administration 3, 4
- Alternative: Acyclovir 400 mg orally 3-5 times daily can be used if valacyclovir is unavailable 1
The higher twice-daily valacyclovir dose (500 mg twice daily) recommended for HIV-infected patients with genital herpes suppression 1 applies to chronic suppressive therapy, not acute treatment of mucocutaneous lesions.
Treatment Duration and Monitoring
Duration must be individualized based on lesion healing, not calendar days:
- Minimum duration: 7-10 days 1, 5
- Critical endpoint: Continue treatment until all lesions have completely healed/crusted 5, 6
- Immunocompromised patients often require extended therapy beyond 10 days because lesions develop over longer periods (7-14 days) and heal more slowly 6
- Without adequate treatment duration, some immunocompromised patients develop chronic ulcerations with persistent viral replication 6
Monitor for treatment failure:
- If lesions do not begin to resolve within 7-10 days, suspect acyclovir resistance 1
- Obtain viral culture with susceptibility testing to confirm resistance 1
- Switch to IV foscarnet 40 mg/kg every 8 hours if resistance is confirmed 1, 2
When to Escalate to Intravenous Therapy
Immediate escalation to IV acyclovir 5-10 mg/kg every 8 hours is required for: 1, 5
- Disseminated HSV (multiple body sites)
- Visceral organ involvement
- Central nervous system involvement
- Inability to tolerate oral medications
- Severe immunosuppression with high risk of dissemination
Renal Dosing Considerations
- Monitor renal function at treatment initiation and once or twice weekly during therapy 6
- Dose adjustments are mandatory for patients with renal impairment to prevent acute renal failure 6
- For high-dose IV acyclovir, monitoring is particularly critical as thrombotic thrombocytopenic purpura/hemolytic uremic syndrome has been reported in HIV-infected patients receiving high-dose valacyclovir (8 grams/day), though not at standard HSV treatment doses 1
Immunosuppression Management
- Consider temporarily reducing immunosuppressive medications if the patient has severe or disseminated HSV infection 5, 6
- Immunosuppression may be restarted after the patient has commenced antiviral therapy and lesions have resolved 5
Common Pitfalls to Avoid
- Do not stop treatment at exactly 7 days if lesions are still active—this is the most common error 6
- Do not use topical antivirals—they are substantially less effective than systemic therapy 6, 2
- Do not assume all immunocompromised patients need IV therapy—localized mucocutaneous disease can be treated orally with close monitoring 1, 7
- Do not delay obtaining viral culture if treatment fails—resistance testing is essential for guiding alternative therapy 1