Neosaxitoxin Combination Formulations for Prolonged Local Anesthesia

摘要

Since each of the site I sodium channel blockers have a unique activity and cannot be used to extrapolate the same effective dosage for another site I sodium channel blocker, studies were conducted to identify dosages of neosaxitoxin (“NeoSTX”) and bupivacaine, alone or in combination with epinephrine, to provide two to three days of pain relief in humans. Bupivacaine-NeoSTX combinations produce more reliable blockade and longer duration blockade compared to NeoSTX alone. The three-way combination of NeoSTX-bupivacaine-epinephrine produces more prolonged local anesthesia than the two-way combination of NeoSTX-bupivacaine. Addition of epinephrine to this NeoSTX-bupivacaine combination dramatically prolongs the duration of complete blockade to a mechanical stimulus. These results led to development of specific combination dosage formulations.