varicella-zoster%20virus%20infection
VARICELLA-ZOSTER VIRUS INFECTION
Treatment Guideline Chart
Varicella, also known as chickenpox, is a self-limited benign disease caused by primary varicella-zoster virus (VZV) infection characterized by fever, malaise, and generalized pruritic vesicular rash.
The average incubation period is 14-16 days. It is transmitted via direct contact with vesicular fluid or inhalation of aerosolized respiratory secretions or via droplet route during face-to-face contact.
Hallmark sign is pruritic rash that begins in the scalp and face which eventually spreads to the trunks and extremities.

Varicella-zoster%20virus%20infection Treatment

Pharmacotherapy

Symptomatic Therapy

Antipruritics

  • Calamine lotion, tepid baths, cool compresses

Antipyretics

  • Eg Paracetamol
    • Aspirin should not be used in children because of its association with Reye’s syndrome
  • Provide symptomatic relief of fever

Analgesics

  • Eg Paracetamol, nonsteroidal anti-inflammatory drugs (NSAIDs); opioids may be considered in severe pain
  • May be used for relief of pain in herpes zoster infections

Corticosteroids

  • Benefits include acute pain reduction and rapid early healing
  • Should be administered with antiviral therapy due to its immunosuppressive properties
    • Concomitant use does not reduce incidence of postherpetic neuralgia (PHN)

Antivirals for Varicella

  • Varicella in otherwise healthy adults and in immunocompromised patients tends to be more severe and they may be treated with antivirals preferably within 24 hours of rash onset
  • Not recommended as prophylaxis after exposure to varicella

Aciclovir [Oral/Intravenous (IV)]

  • Aciclovir is recommended in varicella-zoster virus (VZV) infections in immunocompromised patients and pregnant human immunodeficiency virus (HIV)-infected women with uncomplicated shingles
    • May be considered in patients with chronic cutaneous disorders, in patients with diseases that can be exacerbated by VZV infection (eg cystic fibrosis), otherwise healthy children >12 years or secondary household contacts, adolescents and adults, patients receiving a course of corticosteroids or chronic salicylate therapy
  • Oral therapy should be given within the 1st 24 hours after rash occurs 
  • IV therapy should be used in severely immunocompromised patients, with severe infections and in pregnant women who exhibit signs and symptoms of VZV pneumonitis
    • High-dose oral Aciclovir may be sufficient for mildly immunocompromised patients
    • Show clinical improvement in 48-72 hours
    • Can decrease the risk of contralateral eye involvement when administered for ≥3 months for patients with acute retinal necrosis
  • Actions: A guanosine analogue that is a competitive inhibitor of viral DNA polymerase
    • Limits viral replication and stops further spread of the virus to other cells
  • Effects: Shortens the duration of viral shedding, halts the formation of new lesions more quickly, accelerates the rate of healing in both immunocompetent and immunocompromised patients
    • This improvement is modest in the healthy individual but can reduce life-threatening complications in high-risk individuals

Famciclovir/Valaciclovir

  • Have been used in place of Aciclovir in otherwise healthy adults

Antivirals for Herpes Zoster

  • Oral antiviral therapy is recommended in immunocompetent patients with ophthalmic or other nontruncal dermatomal rash, patients ≥50 years, and in patients suffering moderate to severe pain or rash
  • IV Aciclovir is typically recommended in immunocompromised patients
    • Oral antivirals may be acceptable in patients who are only mildly to moderately immunocompromised
    • IV Foscarnet may be an alternative for Aciclovir-resistant VZV
  • Primary goal of treatment in herpes zoster is to reduce acute pain and PHN
  • Therapy for herpes zoster should accelerate healing, limit the severity and duration of acute and chronic pain, reduce complications
  • When taken within 72 hours of symptom onset, oral antivirals have been shown to reduce severity and duration of symptoms
    • Most viral replication has ceased by 72 hours after the onset of rash but this may be substantially extended in immunocompromised patients
    • After 72 hours, antivirals should be considered if new vesicular lesions are continuing to appear or if complications arise
  • Choice of agent depends on availability, cost, dosing schedule and patient preference
    • Famciclovir or Valaciclovir is preferable to Aciclovir because of convenient dosing and higher antiviral drug activity

Aciclovir

  • Actions: Guanosine analogue that is a competitive inhibitor of viral DNA polymerase
    • Limits viral replication and stops further spread of the virus to other cells
  • Effects: Several studies have shown that high-dose oral Aciclovir accelerates resolution of acute lesions and may reduce the risk for prolonged pain
  • IV Aciclovir should be initiated and continued until clinical improvement of extensive cutaneous lesions or patients with suspected visceral involvement
  • IV route may be shifted oral once no new cutaneous lesions are noted and signs and symptoms are improving

Famciclovir

  • Actions: Diacetyl prodrug of Penciclovir; has higher bioavailability than Penciclovir and is rapidly converted to Penciclovir in gastrointestinal tract (GIT), blood and liver
    • Penciclovir has similar mechanism of action as Aciclovir but has a longer half-life
  • Effects: Efficacy is similar to Aciclovir

Valaciclovir

  • Actions: Valine ester derivative of Aciclovir with improved oral absorption and it is immediately transformed to Aciclovir after absorption
    • Has the same mode of action as Aciclovir
  • Effects: Efficacy is similar to Aciclovir

Alternative Treatment for Herpes Zoster

Brivudine (Brivudin)

  • Actions: A thymidine nucleoside analogue that competitively inhibits viral DNA replication by blocking DNA polymerases
  • A treatment option for immunocompetent patients with herpes zoster
  • Effects: Several studies have shown that patients given Brivudine had shorter time to last new-lesion formation and full crusting, and with less experienced pain

Non-Pharmacological Therapy

Skin/Wound Care

  • Keep skin lesions dry and clean to prevent bacterial superinfection
    • Shower at least twice a day with soap and water
  • Nails should always be trimmed short and kept clean
  • Avoid peeling lesion crust and let it slough off naturally
  • Soft or liquid diet may be preferred for patients with lesions near the mouth
  • Sterile wet dressings may decrease discomfort from lesions
Editor's Recommendations