title: Disopyramide and N-monodesalkyl disopyramide in serum and breast milk.
abstract: Maternal serum and breast milk were obtained to determine the concentration of disopyramide (DP) and its metabolite N-monodesalkyl disopyramide (NMD) from a woman requiring antidysrhythmic drug therapy. Infant serum and urine were also obtained for drug concentrations. DP 450 mg tid resulted in peak maternal serum concentrations of 4.0 micrograms/mL and 2.2 micrograms/mL for DP and NMD, respectively. Breast milk concentrations averaged 1.06 and 6.24 times the serum levels for DP and NMD, respectively. No DP was measurable in the infant's serum except for cord blood, which contained 0.7 micrograms/mL DP, 26 percent of simultaneous maternal concentration, and 0.9 micrograms/mL NMD, which represented 43 percent of the maternal concentration. Infant urine collected over an eight-hour period contained 3.3 micrograms/mL of DP and 3.7 micrograms/mL of NMD.
authors.affiliation: Department of Pharmacy Practice, School of Pharmacy, University of Washington, Seattle 98195.
authors.forename: A J
authors.initials: AJ
authors.lastname: Ellsworth
authors.forename: J R
authors.initials: JR
authors.lastname: Horn
authors.forename: V A
authors.initials: VA
authors.lastname: Raisys
authors.forename: L A
authors.initials: LA
authors.lastname: Miyagawa
authors.forename: J L
authors.initials: JL
authors.lastname: Bell
mesh_terms: D000328:Adult; D004206:Disopyramide / Q000031:analogs & derivatives* / Q000097:blood / Q000378:metabolism*; D005260:Female; D005312:Fetal Blood / Q000032:analysis*; D006801:Humans; D007231:Infant, Newborn; D008431:Maternal-Fetal Exchange; D008895:Milk, Human / Q000032:analysis*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000188:drug therapy; D014693:Ventricular Fibrillation / Q000188:drug therapy
chemical_list: C030438:4-(isopropylamino)-2-(2-pyridyl)-2-phenylbutyramide; D004206:Disopyramide