Transfer of enprofylline into breast milk

Enprofylline concentrations were measured on 3 consecutive days in milk and plasma from six nursing mothers who were treated twice daily with 150-mg enprofylline slow-release tablets. The mean plasma concentration was 0.89 mg/L and the mean milk concentration was 0.71 mg/L, the average milk/plasma ratio being 0.80. The mean milk/plasma ratio ranged from 0.67 to 0.98 in the six mothers. It was estimated that a maximum of approximately 10% of an adult dose of enprofylline, on a per-kilogram body-weight basis, may be transferred to the suckling infant.