ISSN:
1573-904X
Keywords:
controlled release
;
gel
;
lidocaine·HC1
;
nerve block
;
in vitro-in vivo correlation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Purpose. Methods of delaying the action of local anesthetics are important, since short duration of action limits their use in the treatment of postoperative and chronic pain. The present study evaluated the use of low-viscosity gels in prolonging the release of lidocaine. Methods. Release of lidocaine from 2% lidocaine-HC1 containing methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), sodiumcarboxymethyl cellulose (CMC), and poloxamer 407 (PO) gels was studied in phosphate buffer, pH 7.4, at 37°C. Commercial metylcellulose gel (MCcom) served as control. The in vivo efficacy of the respective gel formulations were evaluated in rats. The gel was injected into the vicinity of the sciatic nerve and nociception and motor function were tested. Results. The cumulative amount of lidocaine released during 8 hr was slowest from the PO gel, followed by the CMC, HPMC and MC gels. The antinociceptive effect was not prevented by the motor block and lasted longest with the PO gel. Good linear and rank order correlation was obtained between in vitro and in vivoresults. The microscopic examination of the tissue samples revealed only mild or no irritation of the skeletal muscle tissue by the PO, HPMC, and CMC gels. Conclusions. Based on these results poloxamer gel proved to be the most promising carrier for lidocaine.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1016264527738
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