Desipramine and its metabolite 2-hydroxydesipramine were measured in the
milk of a nursing mother and in the plasma of the mother and infant during
administration of 300 mg/day of desipramine to the mother. Similar
concentrations of both compounds were found in maternal plasma and milk. A
pharmacokinetic plot of the milk over 24 hours showed the expected rise and
fall of the substances following a single nighttime dose. Neither parent
compound nor metabolite could be detected in the infant's serum even though
the measurements were made shortly after peak ingestion by the infant.
Furthermore, no clinical signs of toxicity were observed in the infant
after 3 weeks of treating the mother with desipramine.