Vasoactive properties of lignocaine administered by iontophoresis in human skin

David J. Newton, Alexandra K. B. Amyes, Faisel Khan, Graeme A. McLeod, Jonathan Bannister, Jill J. F. Belch

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

The vasoactivity of lignocaine has an important influence on its clinical efficacy and systemic vascular absorption. The aim of this study was to evaluate its vasoactive properties when administered by the non-invasive technique of iontophoresis. We used laser Doppler imaging to measure the forearm skin blood flow responses of seven healthy young males to iontophoretic delivery of two preparations of 20 g/l of lignocaine hydrochloride, one containing the
preservatives methylparaben and propylparaben and one without. The subjects were blind to the order of drug administration, and we assessed analgesia at the sites using a pinprick test. Delivery of both preparations of (positively charged) lignocaine under the anode caused demonstrable analgesia, but no change in skin blood flow. An increase in perfusion was measured, however, when the preservative-containing preparation was administered under the cathode. There was little or no response to the solution without preservatives, although the difference in response between the two preparations was not statistically significant (P = 0.063). Although there were no vasoactive effects of lignocaine at the relatively low dose used in the present study, our results suggest that the preservatives methylparaben and propylparaben are the most likely cause of the vasodilatation that we observed under the cathode, and may therefore have a significant influence on the vasoactivity of this preparation when administered by injection. Both are negatively charged in solution and have been reported to possess vasodilator properties. It might be worth considering the use of alternative, non-vasoactive preservatives in local anaesthetic preparations, or avoiding the use of additives altogether, when this is feasible.
Original languageEnglish
Pages (from-to)87-92
Number of pages6
JournalClinical Science
Volume104
Issue number1
DOIs
Publication statusPublished - Jan 2003

Fingerprint

Dive into the research topics of 'Vasoactive properties of lignocaine administered by iontophoresis in human skin'. Together they form a unique fingerprint.

Cite this