Skip to content
ClinCalc Pro
Menu
Live attenuated (Varivax/Varilrix/Zostavax) or recombinant subunit (Shingrix)

Varicella-zoster vaccine

Brand names: Varivax, Varilrix, Zostavax, Shingrix

A live attenuated vaccine derived from the varicella-zoster virus, used either to prevent chickenpox (varicella) or, in older adults, to reduce the incidence of shingles (herpes zoster).

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

The attenuated Oka-strain virus induces humoral and cell-mediated immunity against varicella-zoster virus, boosting protection and reducing the risk of viral reactivation.

Prescribing in practice

  • As a live vaccine it is contraindicated in pregnancy and in significant immunosuppression, where a non-live recombinant zoster vaccine should be considered instead.
  • Pregnancy should be avoided for the recommended period after vaccination, and close contact with susceptible immunocompromised individuals managed if a rash develops.
  • Salicylates should be avoided for a period after varicella vaccination in children because of a theoretical risk of Reye's syndrome.

Monitoring

No routine laboratory monitoring is required; observe for injection-site reactions and any post-vaccination varicelliform rash.

Counselling the patient

  • A mild rash or injection-site soreness can occur and usually settles by itself.
  • Avoid becoming pregnant for the advised period after the vaccine.
  • Seek advice if a widespread rash develops, particularly if you are in contact with pregnant or immunocompromised people.

Evidence & guidelines

Use is supported by UK immunisation guidance (the Green Book), which distinguishes the live vaccine from the non-live recombinant zoster vaccine for at-risk groups.

Reference: UKHSA Green Book Ch.28a/34; JCVI; Confirm identity and dosing against the manufacturer SPC (eMC) and NICE. Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.