Herpevex Use In Pregnancy & Lactation

A post- marketing aciclovir pregnancy registry has documented pregnancy outcomes in women exposed to any formulation of Herpevex. The birth defects described amongst Herpevex exposed subjects have not shown any uniqueness or consistent pattern to suggest a common cause.
Caution should however be exercised by balancing the potential benefits of treatment against any possible hazard.
Following oral administration of 200 mg Herpevex five times a day, aciclovir has been detected in breast milk at concentrations ranging from 0.6 to 4.1 times the corresponding plasma levels. These levels would potentially expose nursing infants to aciclovir dosages of up to 0.3 mg/kg/day. Caution is therefore advised if Herpevex is to be administered to a nursing woman. Systemic administration of aciclovir in internationally accepted standard tests did not produce embryotoxic or teratogenic effects in rats, rabbits or mice.
In a non-standard test in rats, foetal abnormalities were observed. But only following such high subcutaneous doses that maternal toxicity was produced. The clinical relevance of these findings is uncertain.