Transfer of escitalopram and its metabolite demethylescitalopram into breastmilk.
OBJECTIVE
To investigate the transfer of escitalopram and its demethyl metabolite into milk, the absolute and relative infant doses via milk and to assess any unwanted effects in the breastfed infant.


METHODS
Multiple samples of blood and milk were obtained over a dose interval at steady state from eight women who were taking escitalopram for postnatal depression. Drug concentrations in plasma and milk were measured by high-performance liquid chromatography and milk/plasma ratio (M/P(AUC)), absolute infant dose and relative infant dose were estimated by standard methods. Their breastfed infants were also examined clinically and in five infants a blood sample was taken for drug analysis.


RESULTS
The median dose taken by the women was 10 mg day(-1). The mean (95% confidence interval) M/P(AUC) was 2.2 (2.0, 2.4) for escitalopram and 2.2 (1.9, 2.5) for demethylescitalopram. Absolute infant doses were 7.6 microg kg(-1) day(-1) (5.2, 10.0) for escitalopram and 3.0 microg kg(-1) day(-1) (2.4, 3.6) for demethylescitalopram. The total relative infant dose for escitalopram plus its demethyl metabolite was 5.3% (4.2, 6.4) as escitalopram equivalents. All of the infants had met normal developmental milestones and no adverse effects were seen. Compared with average maternal plasma concentrations (24 microg l(-1)), the concentrations of the parent drug and its metabolite in plasma from five infants were most commonly below the limit of detection (</=3 microg l(-1)).


CONCLUSIONS
The study shows that escitalopram is safe for use during breastfeeding. Because its absolute infant dose is lower than that for an equivalent antidepressant dose of rac-citalopram, it may be preferred over rac-citalopram in treating depression in lactating women. Nevertheless, each decision to breastfeed should always be made on the basis of an individual risk:benefit analysis.
Rampono
Jonathan
J
Department of Psychological Medicine, Women's and Children's Health Service, Subiaco, Australia.
Hackett
L Peter
LP
Kristensen
Judith H
JH
Kohan
Rolland
R
Page-Sharp
Madhu
M
Ilett
Kenneth F
KF
D000328:Adult; D000928:Antidepressive Agents / Q000378:metabolism / Q000493:pharmacokinetics*; D018687:Antidepressive Agents, Second-Generation / Q000493:pharmacokinetics*; D001942:Breast Feeding; D015283:Citalopram / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008895:Milk, Human / Q000737:chemistry*
D000928:Antidepressive Agents; D018687:Antidepressive Agents, Second-Generation; C518844:demethylescitalopram; D015283:Citalopram