Water/oil type microemulsion systems containing lidocaine hydrochloride: in vitro and in vivo evaluation

Dogrul A., Arslan S. A. , Tirnaksiz F.

JOURNAL OF MICROENCAPSULATION, cilt.31, sa.5, ss.448-460, 2014 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 31 Konu: 5
  • Basım Tarihi: 2014
  • Doi Numarası: 10.3109/02652048.2013.879926
  • Sayfa Sayıları: ss.448-460


The purpose of this study was to develop a water/oil microemulsion containing lidocaine hydrochloride (4%) and to compare its local anaesthetic efficacy with commercial products. A pseudoternary diagram (K-m: 1/1 or 1/2) was constructed using lecithin/ethanol/oil/water. The droplet size, viscosity and release of the microemulsions were evaluated. Tail flick tests were conducted for in vivo effectiveness; the initiation time of effect, maximum effect, time to reach maximum effect, and relative efficacy were evaluated. The drug caused a significant increase in droplet size. The use of olive oil resulted in a decrease in the solubilisation parameter, as well as a reduction in the release. The droplet size and viscosity of the microemulsion composed of Miglyol/lecithin/ethanol/water/drug (K-m: 1/2) was lower than other microemulsions (8.38 nm, 6.9 mPa), and its release rate (1.61 mg/h) was higher. This system had a faster and more efficient anaesthetic effect than the other microemulsions and commercial products. Results indicate that a water/oil type microemulsion (Miglyol/lecithin/ethanol/water) has promising potential to increase the local anaesthetic effect.