Maternal Levels. A woman taking fluconazole 200 mg orally once daily for 18 days had a peak milk level of 4.1 mg/L 2 hours after the dose on day 20 postpartum. The half-life of elimination from breastmilk was 26.9 hours.[8]
A 12-week postpartum woman was given a single oral dose of fluconazole 150 mg. The highest milk levels were 2.9 and 2.7 mg/L at 2 and 5 hours after the dose. Milk fluconazole levels were 1.8 and 1 mg/L at 24 and 48 hours after the dose, respectively. The half-life in milk was about 30 hours.[9]
Using peak milk level data from these two patients, an exclusively breastfed infant whose mother was taking 200 mg daily of fluconazole would receive a maximum of about 0.6 mg/kg daily, which is 60% of the recommended neonatal (