Transfer of Cyclobenzaprine into Human Milk and Subsequent Infant Exposure

J Hum Lact. 2019 Aug;35(3):559-562. doi: 10.1177/0890334419843307. Epub 2019 Apr 24.

Abstract

Introduction: Cyclobenzaprine is a skeletal muscle relaxant primarily used in the treatment of pain. Its use during lactation is a matter of concern as its level of exposure to infants through human milk is still unknown.

Main issue: The aim of this study was to determine cyclobenzaprine concentrations in the milk samples collected from two lactating mothers.

Management: The present study describes the analysis of cyclobenzaprine in human milk using liquid chromatography mass spectrometry, which determined the drug concentration-time profiles in human milk.

Conclusion: This study shows low levels of concentrations of cyclobenzaprine in human milk with calculated relative infant dose of 0.5%. However, due to the sedative properties of cyclobenzaprine, regular clinical assessment of the infant is recommended to evaluate for long-term effects.

Keywords: Breastfeeding; human milk; lactation; maternal health; mother-to-child transmission.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Amitriptyline / adverse effects
  • Amitriptyline / analogs & derivatives*
  • Amitriptyline / pharmacokinetics
  • Breast Feeding*
  • Diagnosis, Differential
  • Female
  • Humans
  • Infant, Newborn
  • Mass Spectrometry
  • Milk, Human / chemistry*
  • Milk, Human / metabolism
  • Muscle Relaxants, Central / adverse effects*
  • Muscle Relaxants, Central / pharmacokinetics
  • Pain / drug therapy*
  • Pregnancy
  • Prenatal Care*

Substances

  • Muscle Relaxants, Central
  • Amitriptyline
  • cyclobenzaprine