What is a better alternative to oral valacyclovir (valacyclovir) if it doesn't work?

Alternatives to Oral Valacyclovir for Herpes Treatment

If oral valacyclovir doesn't work, famciclovir is the best alternative, followed by acyclovir; for resistant cases, intravenous foscarnet should be used. 1

First-Line Alternatives

When valacyclovir fails to provide adequate clinical response, consider these alternatives:

• Famciclovir: An effective oral alternative with good bioavailability

  • For episodic treatment: 125 mg twice daily for 5 days 1
  • For suppressive therapy: 250 mg twice daily 1
  • Note: Some studies suggest valacyclovir may be somewhat more effective than famciclovir for suppression of viral shedding 2

• Oral Acyclovir: The parent compound of valacyclovir

  • For episodic treatment: 400 mg three times daily for 5 days, or 200 mg five times daily for 5 days, or 800 mg twice daily for 5 days 1
  • For suppressive therapy: 400 mg twice daily 1
  • Requires more frequent dosing than valacyclovir but has similar clinical efficacy 3

For Resistant Cases

If resistance to valacyclovir is suspected (persistent lesions despite adequate treatment):

• Important: All acyclovir-resistant strains are also resistant to valacyclovir, and most are resistant to famciclovir 1

• Foscarnet: 40 mg/kg IV every 8 hours until clinical resolution 1

  • First-line treatment for proven or suspected acyclovir-resistant strains
  • Requires intravenous administration and monitoring

• Topical cidofovir gel 1%: Applied to lesions once daily for 5 consecutive days 1

  • Alternative for resistant cases
  • May be used as adjunctive therapy

Special Considerations

For Immunocompromised Patients

• Higher doses of oral antivirals are often beneficial 1

  • Acyclovir: 400 mg orally three to five times daily 1
  • Famciclovir: 500 mg twice daily (shown effective in reducing recurrences and subclinical shedding in HIV patients) 1
  • Continue therapy until clinical resolution 1

• For severe cases: Intravenous acyclovir 5 mg/kg every 8 hours 1

For Ocular Herpes

• Higher doses may be required:
  • Oral acyclovir (400 mg five times daily), valacyclovir (500 mg three times daily), or famciclovir (250 mg twice daily) 1
  • For unresponsive cases, consider topical antivirals as adjunctive treatment 1

Monitoring and Follow-up

• Patients should be evaluated within 1 week of treatment initiation 1
• If lesions persist despite adequate treatment with alternative antivirals, suspect viral resistance 1
• Consider consultation with an infectious disease specialist for resistant cases 1

Pitfalls to Avoid

• Don't continue ineffective therapy: If valacyclovir fails, switching to another antiviral class (foscarnet) is necessary for resistant cases rather than increasing valacyclovir dose 1
• Don't overlook immunocompromise: Treatment failure may indicate underlying immune dysfunction requiring higher doses or IV therapy 1
• Don't forget compliance issues: Valacyclovir failure may be due to poor adherence; famciclovir and acyclovir require more frequent dosing which could further impact compliance 4
• Don't miss resistance: Persistent lesions despite adequate therapy should prompt consideration of resistance testing and alternative treatments 1