Is Valacyclovir Safe in Breastfeeding

I am a breastfeeding mother and i want to know if it is safe to use Valacyclovir? Is Valacyclovir safe for nursing mother and child? Does Valacyclovir extracts into breast milk? Does Valacyclovir has any long term or short term side effects on infants? Can Valacyclovir influence milk supply or can Valacyclovir decrease milk supply in lactating mothers?

Precursor of Aciclovir which is used for treatment of infections due to Herpes zoster and Herpes simplex viruses and the prevention of Cytomegalovirus infection in immunocompromised patients. It is excreted into breast milk as Aciclovir in non-significant clinical amount, with no side-effects observed among breastfed infants from treated mothers. Urine levels of Aciclovir in those infants were shown to be very low.

The dosage of acyclovir in milk after valacyclovir is less than 1% of a typical infant dosage and would not be expected to cause any adverse effects in breastfed infants. No special precautions are required when using valacyclovir during breastfeeding. In one study, administration of valacyclovir to mothers with concurrent herpes simplex type 2 and HIV infections reduced breastmilk shedding of the HIV virus in breastmilk at 6 and 14 weeks postpartum, but not later.[1] In another study in HIV-positive mothers, valacyclovir did not reduced breastmilk shedding of cytomegalovirus (CMV) or infant CMV acquisition.[2]

In a study of pregnant women with concurrent HIV and Herpes simplex infections, mothers received zidovudine 300 mg daily from week of pregnancy until 12 months postpartum and nevirapine at delivery. Half of the women (n = 74) also received valacyclovir 500 mg orally twice daily from 34 weeks gestation until 12 months postpartum. At 6 weeks postpartum, all infants who received acyclovir in breastmilk had normal serum creatinine (<0.83 mg/dL). Their median serum creatinine and alanine aminotransferase (ALT) values, and growth were no different from those of unexposed infants, with the exception of one infant with an ALT level of 70.1 units/L. Infants whose mothers received valacyclovir generally had adverse effects that were similar to the placebo group, except that treated infants had a lower risk of eczema and oral thrush than infants in the placebo arm.[1][4]