What is the diagnosis and treatment for a 35-year-old male with a widespread disseminated vesicular rash, who returned from India on May 4, 2025, received a flu vaccine on October 4, 2025, has a vesicle swab DNA positive for Varicella (chickenpox) DNA, IgG (Immunoglobulin G) positive for varicella, IgM (Immunoglobulin M) negative, and is commenced on antivirals Valaciclovir (valacyclovir) 2 tablets three times a day?

From the Guidelines

This patient should continue valaciclovir 2 tabs TDS as the current treatment is appropriate for reducing varicella-associated morbidity and mortality, particularly given the widespread disseminated nature of the rash. The positive Varicella DNA from the vesicle swab and IgG positive for varicella, IgM negative results indicate a reactivation of the varicella-zoster virus, which is consistent with the clinical presentation of a disseminated vesicular rash 1.

Key Considerations

• The patient's recent travel history to India and flu vaccination are likely unrelated to the current condition, as the positive IgG and negative IgM indicate past infection rather than a new one.
• Antiviral therapy with valaciclovir is crucial in reducing the severity of the disease, especially in immunocompetent individuals 1.
• Pain management with acetaminophen or NSAIDs may be necessary to alleviate discomfort associated with the rash.
• It is essential to advise the patient to keep lesions covered until they crust over to prevent transmission to susceptible individuals, such as pregnant women, immunocompromised people, and those without a history of chickenpox.
• Close monitoring for secondary bacterial infection of lesions is recommended, and if severe pain develops after lesions heal (postherpetic neuralgia), additional pain management strategies may be necessary.

Treatment and Prevention

• The current treatment with valaciclovir should be continued for the recommended duration, typically 7 days, to ensure optimal outcomes.
• The patient should be educated on the importance of keeping lesions covered and avoiding contact with susceptible individuals to prevent transmission.
• If the patient develops severe pain or secondary bacterial infection, prompt medical attention and adjustment of the treatment plan may be necessary.

From the FDA Drug Label

CLINICAL STUDIES SECTION 14. 3 Herpes Zoster Two randomized double-blind clinical trials in immunocompetent adults with localized herpes zoster were conducted. The patient has a widespread disseminated vesicular rash and is DNA positive for Varicella DNA, indicating a diagnosis of varicella (chickenpox). The patient is being treated with valaciclovir.

• The valaciclovir drug label does provide information on the treatment of herpes zoster (shingles), but it does not directly address the treatment of varicella (chickenpox) in immunocompetent adults.
• However, varicella and herpes zoster are both caused by herpesviruses, and valaciclovir is an antiviral medication that is effective against these viruses.
• Given the patient's diagnosis and the fact that valaciclovir is being used to treat varicella, it is likely that the treatment is intended to reduce the severity and duration of the illness.
• The patient's IgG positive status for varicella indicates that they have had a previous infection, but the presence of IgM negative status suggests that this is not a new infection.
• The use of valaciclovir in this patient is likely based on clinical judgment and experience, rather than direct evidence from the drug label [ 2 ].

From the Research

Patient Profile

• 35-year-old male with widespread disseminated vesicular rash
• Returned from India on 5/4/25
• Received flu vaccine on 10/4/25
• Vesicle swab DNA positive for Varicella DNA
• IgG positive for varicella, IgM negative
• Commenced on Antivirals valaciclovir 2 tabs TDS

Treatment with Valaciclovir

• Valaciclovir is an effective treatment for herpes zoster in immunocompetent adults 3, 4, 5
• The recommended regimen for the treatment of herpes zoster is 1000 mg 3 times daily for 7 days 3, 4
• Valaciclovir has been shown to be at least as effective as aciclovir in controlling the symptoms of acute herpes zoster 3, 4
• Valaciclovir alleviates zoster-associated pain and postherpetic neuralgia significantly faster than aciclovir 3

Dosage and Efficacy

• A study comparing different dosages of valaciclovir for the treatment of herpes zoster in adults found that high-dose valaciclovir (900 mg three times daily for 10 days) was more effective than low-dose valaciclovir (300 mg two times daily for 10 days) in reducing pain and incidence of postherpetic neuralgia in middle-aged and elderly patients 6
• The study also found that the difference in visual analog scale (VAS) pain scores between the two dose groups was statistically significant in middle-aged and elderly patients at the 6th day 6

Safety and Tolerability

• Valaciclovir is well tolerated, with nausea and headache being the most commonly reported adverse events 3, 4, 5
• The safety profile of valaciclovir is similar to that of aciclovir or placebo 3, 4, 5
• A study found that the incidence of adverse reactions was not statistically significant between high-dose and low-dose valaciclovir groups 6