Table of Contents
ISRN Pharmaceutics
Volume 2011, Article ID 582351, 6 pages
Research Article

Pharmacokinetic Compatibility Study of Lidocaine with EXPAREL in Yucatan Miniature Pigs

1Clinical Research & Drug Safety Assessment, Pacira Pharmaceuticals Inc., San Diego, CA 92121, USA
2Raleigh, NC 27613, USA
3ABC Laboratories, Columbia, MO 65201, USA
4Sinclair Research Center, LLC, Auxvasse, MO 65231, USA

Received 9 August 2011; Accepted 27 September 2011

Academic Editors: G. M. El Maghraby, J. K. Lalla, M. Moneghini, A. I. Segall, A. Shahiwala, and J. Torrado

Copyright © 2011 Brigitte M. Richard et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We explored the potential for EXPAREL to interact with lidocaine. Sixty (60) male Yucatan Swine were randomized into 20 groups ( 𝑁 = 3 /group). EXPAREL (2 or 4 mg/kg) and/or lidocaine HCl solution 1% or 2% (with epinephrine 1 : 200,000) were injected subcutaneously along a 5 cm virtual incision line. The effects on the pharmacokinetics of bupivacaine and lidocaine were examined when 5, 10, 20, and 40 minutes had passed between administration of lidocaine and EXPAREL. Systemic exposure to lidocaine was increased ( A U C 0 2 4 h r by 48%; 𝐶 m a x by 1,640%) when lidocaine (4 mg/kg) was followed 5 minutes later by EXPAREL (4 mg/kg) compared to lidocaine administered alone. Plasma bupivacaine was increased ( A U C 0 2 4 h r by 50–95%; 𝐶 m a x by 67–1,000%) when lidocaine (4 mg/kg) was followed 5 or 10 minutes later by EXPAREL (4 mg/kg) compared to EXPAREL alone. While EXPAREL should not be admixed with lidocaine, this study shows that local administration of EXPAREL after at least 20 minutes following local administration of lidocaine did not increase the release of either drug.