Pharmacokinetics of indomethacin in pregnancy

Erik Rytting, Tatiana N. Nanovskaya, Xiaoming Wang, Daria I. Vernikovskaya, Shannon M. Clark, Marlo Cochran, Susan M. Abdel-Rahman, Raman Venkataramanan, Steve N. Caritis, Gary D.V. Hankins, Mahmoud S. Ahmed

Research output: Contribution to journalArticle

12 Scopus citations


Background and objectives: Although indomethacin has been widely used for the treatment of preterm labor over the past 40 years, there are few reports regarding its pharmacokinetics in pregnant women. Methods: This opportunistic study assessed the steady-state pharmacokinetics of indomethacin in pregnant subjects to whom an oral dose of 25 mg every 6 h was prescribed. Indomethacin concentrations in plasma and urine were analyzed by a validated high-performance liquid chromatography method with mass spectrometric detection. Results: The mean area under the plasma concentration versus time curve at steady state (AUCss) was 1.91 ± 0.53 μg·h/mL, mean peak plasma concentration (C max) was 1.02 ± 0.49 μg/mL, and mean time to reach C max (t max) was 1.3 ± 0.7 h. The mean apparent clearance at steady state was 14.5 ± 5.5 L/h, which is higher than the apparent clearance reported in the literature for non-pregnant subjects. Indomethacin crosses the placenta; the mean fetal/maternal ratio from five sets of cord blood samples collected at delivery was 4.0 ± 1.1. Conclusions: Further studies are needed to determine whether any dose adjustments are necessary as a result of the increased clearance of indomethacin during pregnancy.

Original languageEnglish (US)
Pages (from-to)545-551
Number of pages7
JournalClinical Pharmacokinetics
Issue number6
StatePublished - Jun 2014


ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)

Cite this

Rytting, E., Nanovskaya, T. N., Wang, X., Vernikovskaya, D. I., Clark, S. M., Cochran, M., Abdel-Rahman, S. M., Venkataramanan, R., Caritis, S. N., Hankins, G. D. V., & Ahmed, M. S. (2014). Pharmacokinetics of indomethacin in pregnancy. Clinical Pharmacokinetics, 53(6), 545-551.