Is Lamivudine Safe in Breastfeeding

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

Anti-HIV, Anti HBV. It has been used to treat newborns and children.

Lamivudine has not been studied in HIV-negative nursing mothers being treated for hepatitis B infection, but the low doses used would not be expected to cause any serious adverse effects in breastfed infants. The manufacturer estimates that a breastfed infant's dose would be about 6% of the infant dose for children over 2 years of age. An expert review of available data concluded that there is currently no justification for contraindicating the use of lamivudine for hepatitis B therapy during breastfeeding.[1] Some professional organization guidelines allow breastfeeding during lamivudine therapy, although one guideline cautions against it because of a lack of long-term safety data.[2][3][4] The lack of long-term safety data with long-term, low-level infant exposure should be discussed with the mother.[2] No differences exist in infection rates between breast-fed and formula-fed infants born to hepatitis B-infected women, as long as the infant receives hepatitis B immune globulin and hepatitis B vaccine at birth. Mothers with hepatitis B are encouraged to breastfeed their infants after their infants receive these preventative measures.[5][6] In the United States and other developed countries, HIV-infected mothers should generally not breastfeed their infants. In countries in which no acceptable, feasible, sustainable and safe replacement feeding is available, World Health Organization guidelines recommend that all women with an HIV infection who are pregnant or breastfeeding should be maintained on antiretroviral therapy for at least the duration of risk for mother-to-child transmission. Mothers should exclusively breastfeed their infants for the first 6 months of life; breastfeeding with complementary feeding should continue through at least 12 months of life up to 24 months of life.[7] The first choice regimen for nursing mothers is tenofovir, efavirenz and either lamivudine or emtricitabine. If these drugs are unavailable, alternative regimens include: 1) zidovudine, lamivudine and efavirenz; 2) zidovudine, lamivudine and nevirapine; or 3) tenofovir, nevirapine and either lamivudine or emtricitabine. Exclusively breastfed infants should also receive 6 weeks of prophylaxis with nevirapine.[8][9]

A study assigned pregnant women to zidovudine alone or highly active antiretroviral therapy (HAART: zidovudine, lamivudine and nevirapine) to prevent maternal-to-child transmission of HIV infection. After delivery, all infants received one month of zidovudine prophylaxis; some infants were breastfed and others were formula fed. A higher percentage of infants in the HAART-exposed group had neutropenia than those in the unexposed group at 1 month of age (15.9% and 3.7%, respectively). Hematologic toxicity was transient and asymptomatic. From 2 to 6 months postpartum, no differences in hematologic toxicity were seen between breastfed and formula-fed infants. No statistical difference in hepatic toxicity was seen between the breastfed and formula-fed infants.[24] Twenty-four infants who were breastfed by HIV-positive mothers developed HIV infection by 6 months of age. Six of these infants had a mutation that might have been selected for by subtherapeutic levels of lamivudine in breastmilk.[25] An HIV-positive mother took a combination tablet containing dolutegravir 50 mg, abacavir sulfate 600 mg and lamivudine 300 mg (Triumeq) once daily. Her infant was exclusively breastfed for about 30 weeks and partially breastfed for about 20 weeks more. No obvious side effects were noted.[26] One mother took lamivudine for 33 days, 25 before birth and eight days postpartum for chronic hepatitis B infection. Her infant was breastfed (extent not stated). At three months of age, the infant died with the death attributed to sudden infant death syndrome. The death was unlikely to be related to lamivudine.[27]

Some case reports and in vitro studies have suggested that protease inhibitors might cause hyperprolactinemia and galactorrhea in some male patients,[28][29] although this has been disputed.[30] One case series found an incidence of gynecomastia of 2.4 cases per person annually among men receiving highly active antiretroviral therapy; 51% of the affected patients were taking lamivudine. Gynecomastia was unilateral initially, but progressed to bilateral in 53% of cases. No alterations in serum prolactin were noted and spontaneous resolution usually occurred within one year, even with continuation of the regimen.[31] The relevance of these findings to nursing mothers is not known. The prolactin level in a mother with established lactation may not affect her ability to breastfeed.