Public Health England (PHE) has recommended that women more than 20 weeks pregnant, who are then exposed to chicken pox, should be given aciclovir as post-exposure prophylaxis.
PHE have recommended aciclovir 800mg four times a day from days seven to 14 after exposure, in women 20 weeks pregnant. Valaciclovir 1,000mg three times a day can be used as an alternative.
As aciclovir is not recommended in pregnancy, PHE acknowledge that use of the drug for this indication would be off-label.
But they add that there has been ‘extensive evidence’ of safety in pregnancy, and that the recommended dose is in line with Royal College of Paediatrics and Child Health advice.
The guidance also applies for immunosuppressed women, who should be given aciclovir or valaciclovir if presenting with chicken pox more than 20 weeks into a pregnancy.
The updated advice follows the body’s guidance from July, which restricted use of the VZIG vaccine to pregnant women exposed to chicken pox or shingles within the first 20 weeks due to a national shortage of the vaccine. PHE have now extended those restrictions to immunosuppressed patients.