Dissolving microneedles to obtain rapid local anesthetic effect of lidocaine at skin tissue

Abstract

Dissolving microneedles (DMs) were applied to lidocaine for local anesthesia of the skin. Three DM array chips were prepared where lidocaine was localized at the acral portion of DMs (type 1), loaded in whole DMs (type 2), and lidocaine was loaded both in whole DMs and the chip (type 3). DM chips were 15-mm diameter with 225 DMs, each 500-μm long with a 300-μm diameter base. The lidocaine contents were (type 1) 0.08 ± 0.01 mg, (type 2) 0.22 ± 0.01 mg and (type 3) 8.52 ± 0.49 mg. Lidocaine was released from type 1 and 2 DM array chips within 10 min. Pharmacological activity of DMs were compared to lidocaine cream by the suppression of idiospasm of hair-removed rat skin. Type 1, 2 and 3 DMs showed faster onset time, 5 min, than lidocaine cream. Type 2 and 3 DMs showed stronger anti-idioplasmic activity than type 1 DMs. Pharmacokinetic study showed that tissue lidocaine levels, 62.8 ± 3.6 (type 1), 89.1 ± 9.9 (type 2) and 131.2 ± 10.2(type 3) μg/g wet weight at 5 min after the removal of DM were obtained higher than lidocaine cream, 26.2 ± 12.5 μg/g wet weight. Those results suggest the usefulness of type 2 DMs to obtain fast onset time for the local anesthesia in the skin.

A novel local anesthetic system: transcriptional transactivator peptide-decorated nanocarriers for skin delivery of ropivacaine

“…Important pharmacokinetics profiles of TAT-RVC/NCs, RVC/NCs, and RVC/IJ groups were evaluated 32. Rats were randomly divided into three groups (n=6 each) as follows: 1) TAT-RVC/NCs group; 2) RVC/NCs group; and 3) RVC/IJ group.…”

Lidocaine carboxymethylcellulose with gelatine co-polymer hydrogel delivery by combined microneedle and ultrasound

“…Research has shown significant increases in skin permeability using optimized MNs when considering factors of MN length, number of MNs, the length and width aspect ratio and surface area (Al-Qallaf & Das, 2008Olatunji et al, 2012Olatunji et al, , 2013Guo et al, 2013). It has been suggested that MNs can be adapted to aid lidocaine delivery yielding many fold increase in delivery rate (Kwon, 2004;Li et al, 2008;Wilson et al, 2008;Zhang et al, 2012a, b;Kochhar et al, 2013;Ito et al, 2013;Nayak et al, 2014).…”

Effect of Microneedle Pretreatment on Topical Anesthesia

“…These results are clinically significant since topical lidocaine cream, 4%, is typically used to produce anesthesia 60 minutes after application. 4,6 Our results suggest that the use of microneedle pretreatment can reduce the incubation time to 30 minutes-perhaps even to 10 minutes in more pain-sensitive individuals-to achieve sufficient anesthesia for needle insertion.…”

“…Microneedles are microscopic needles capable of creating microchannels through the stratum corneum to improve transdermal drug delivery. [1][2][3] Microneedles have been shown 1,2,[4][5][6] to enhance the delivery of topical anesthetics with use of in vitro and animal models. In this split-body, randomized clinical trial, we investigated whether pretreatment with microneedles enhanced the anesthetic effect produced by topical lidocaine cream, 4%.…”

“…Limited information exists on the activity and impact of hospitalist dermatology consultative services or the nature of dermatologic issues affecting inpatients across US academic medical centers. [1][2][3][4] We performed a retrospective,…”