Clinical Pharmacology
SCANDONEST stabilizes the neuronal membrane and prevents the initiation and transmission of nerve impulses, thereby effecting local anesthesia.
SCANDONEST is rapidly metabolized, with only a small percentage of the anesthetic (5 to 10 percent) being excreted unchanged in the urine. SCANDONEST, because of its amide structure, is not detoxified by the circulating plasma esterases. The liver is the principal site of metabolism, with over 50 percent of the administered dose being excreted into the bile as metabolites. Most of the metabolized mepivacaine is probably resorbed in the intestine and then excreted into the urine since only a small percentage is found in the feces. The principal route of excretion is via the kidney. Most of the anesthetic and its metabolites are eliminated within 30 hours. It has been shown that hydroxylation and N-demethylation, which are detoxification reactions, play important roles in the metabolism of the anesthetic. Three metabolites of mepivacaine have been identified from adult humans: two phenols, which are excreted almost exclusively as their glucuronide conjugates, and the N-demethylated compound (2', 6'-pipecoloxylidide).
The onset of action is rapid (30 to 120 seconds in the upper jaw; 1 to 4 minutes in the lower jaw) and SCANDONEST 3% PLAIN will ordinarily provide operating anesthesia of 20 minutes in the upper jaw and 40 minutes in the lower jaw.
SCANDONEST 2% L with levonordefrin 1:20,000 provides anesthesia of longer duration for more prolonged procedures, 1 hour to 2.5 hours in the upper jaw and 2.5 hours to 5.5 hours in the lower jaw.
SCANDONEST does not ordinarily produce irritation or tissue damage.
Levonordefrin is a sympathomimetic amine used as a vasoconstrictor in local anesthetic solutions. It has pharmacologic activity similar to that of epinephrine but it is more stable than epinephrine. In equal concentrations, levonordefrin is less potent than epinephrine in raising blood pressure, and as a vasoconstrictor.
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