Pharmacological Study on Increase Factor of Local Anesthetic Effects in Prilocaine Hydrochloride.

Bibliographic Information

Other Title
  • 塩酸プリロカインの局所麻酔効力の増強因子に関する薬理学的研究

Search this article


Local anesthetic potency is markedly modified by the chemical properties of the local anesthetic solution. However, there are no experimental reports distinguishing among local anesthetic solutions of varying osmotic pressures and pH values. Therefore, in this study, in order to increase local anesthetic potency and reduce the local irritation of prilocaine-HCl, we investigated the effects of varying the pH and osmotic pressure of this solution in: (1) the infiltration potency in guinea-pig gingiva, and (2) the inhibition effects of prilocaine-HCl on tibialis contraction induced by electrical stimulation of the sciatic nerve.<BR>An osmotic pressure of 308 mOSM was optimal for maintaining a higher local anesthetic potency, compared with pressures of 280 mOSM and 380 mOSM. At pH 7.4, the depth of anesthesia was increased approximately 1.6 times, and the duration of anesthesia by 1.7 times, compared with at pH 5.0.<BR>When the effect of sodium bicarbonate was tested in infiltration anesthesia in guinea-pig gingiva at pH 7.0 and 7.4, no significant difference was found between the solutions to which sodium bicarbonate was added and those without it. Overall, there were significant differences when the solutions of pH 5.0 and 7.4 were compared with the control solution of pH 6.6, when inhibition effects on sciatic-nerve stimulation were tested. The same tendencies were also observed for the infiltration anesthesia of prilocaine-HCl. The irritation of this anesthetic on porcine cornea was marked at a low pH and decreased with increasing pH.<BR>These results suggest that prilocaine-HCl has a maximum potency and minimum irritation at pH 7.4 and 308 mOSM. Moreover, the addition of sodium bicarbonate is not essential for enhancing the potency of prilocaine-HCl.



See more

Details 詳細情報について

Report a problem

Back to top