Epivir (lamivudine) and Viread (tenofovir) are likely safe for women to use while breast-feeding, Reuters Health reports. Research has shown that both antiretrovirals are safe and effective against hepatitis B virus (HBV) during pregnancy, but questions have remained about safety during breast-feeding. In fact, the label of each drug recommends against taking them while nursing. Publishing their findings in Clinical Infectious Diseases, researchers conducted a review of available research on the drugs during breast-feeding.

Both Epivir and Viread are also active against HIV.

The studies showed that infants’ exposure to Epivir and Viread is much lower through breast-feeding than when they are in the womb.

One study conducted in Malawi found that the concentration of Epivir in breast-fed infants was just 3.7 percent of the mother’s level. Another study in Kenya found that the daily dose of Epivir infants received through breast milk was 2 percent of the daily dose recommended for babies older than 3 months of age.

In a study of women in the Ivory Coast, in which they received one tablet of Viramune (nevirapine) plus two tablets of Viread at the beginning of labor and a combination of Viramune and Viread for seven days after delivery, found that the maximum concentration of Viread in their breast milk was 14.1 nanograms per milliliter. This amount proved lower than in the mother’s blood or cord blood, and it meant that the infant was receiving 0.03 percent of the recommended dose for a newborn. Another study, conducted in Malawi and Brazil, found that the Viread levels in breast milk two days after a two-tablet dose of Viread during labor were 6.3 to 17.8 ng/mL.

The researchers concluded that their findings suggest there should not be a recommendation against breast-feeding while taking Epivir or Viread. However, they believe that long-term studies are needed.

To read the Reuters story, click here.

To read the study abstract, click here.