From the Guidelines
For a patient with worsening shingles despite valacyclovir treatment, the next steps should include switching to intravenous acyclovir (5-10 mg/kg every 8 hours for 7-10 days) as the primary treatment modification, as recommended for complicated herpes zoster (HZ) cases 1. This approach is based on the most recent guidelines, which suggest that treatment for complicated HZ, including cases that worsen despite initial treatment, should involve intravenous acyclovir 1. The decision to switch from valacyclovir to intravenous acyclovir is critical for managing severe or worsening shingles, especially in immunocompromised patients who may require more aggressive antiviral therapy.
Key considerations in managing worsening shingles include:
- Evaluating for potential complications such as secondary bacterial infections, disseminated disease, or ocular involvement, which may require additional treatments like antibiotics 1.
- Optimizing pain management with medications such as gabapentin, pregabalin, tricyclic antidepressants, or opioids if necessary, as well as considering topical treatments like lidocaine patches or capsaicin cream for additional relief.
- Assessing the patient's immune status, as immunosuppressed patients may need more intensive antiviral therapy and consideration of withholding immunosuppressive therapy in severe cases of varicella or herpes zoster infection 1.
The persistence of lesions despite appropriately dosed antiviral therapy should raise suspicion of antiviral resistance, and treatment failure could also be due to delayed initiation of therapy, inadequate dosing, or underlying immunosuppression 1. Therefore, early intervention and adjustment of the treatment plan based on the patient's response and clinical presentation are crucial for preventing complications like postherpetic neuralgia.
From the FDA Drug Label
In subjects aged greater than 50 years, the median time to cessation of new lesions was 3 days in subjects treated with either VALTREX or oral acyclovir The FDA drug label does not answer the question.
From the Research
Treatment Options for Shingles Worsening Despite Valacyclovir Treatment
- If a patient's shingles worsen despite treatment with valacyclovir, the next steps may involve considering alternative antiviral medications or adjusting the current treatment regimen 2.
- Famciclovir has been shown to be effective in reducing the duration of postherpetic neuralgia, a common complication of herpes zoster, and may be considered as an alternative treatment option 3.
- In some cases, a longer duration of treatment with valacyclovir may be necessary to achieve optimal results, as evidenced by a study that found a 12-month course of suppressive treatment with valacyclovir reduced the prevalence and severity of postherpetic neuralgia 4.
Considerations for Treatment Failure
- If valacyclovir treatment fails, it is essential to reassess the patient's condition and consider other potential causes of treatment failure, such as resistance to the medication or underlying immunocompromised status 5.
- In cases of treatment failure, alternative antiviral medications such as foscarnet or cidofovir may be considered, although these medications are typically reserved for more severe or resistant cases 5.
Importance of Early Treatment
- Early initiation of antiviral treatment is crucial in managing herpes zoster and reducing the risk of complications such as postherpetic neuralgia 2, 6.
- Delaying treatment beyond 72 hours after rash onset may reduce the effectiveness of valacyclovir, although it may still be beneficial in some cases 2.