IONTOPHORETIC ADMINISTRATION OF 2-PERCENT-LIDOCAINE-HCL AND 1 100,000-EPINEPHRINE IN HUMANS/

Objective: The primary objective was to evaluate the clinical safety a nd effectiveness of the iontophoretic administration of lidocaine HCl 2% and epinephrine 1:100,000 to induce local dermal anesthesia before intravenous (IV) cannulation. Design: Section I: Open, nonblinded. Sec tion II: Randomized, double-blind, placebo-controlled. Setting: Sectio n I: Healthy adult volunteers. Section II: Patients presenting for sch eduled outpatient eye surgery. Patients: Section I: Seven healthy adul t volunteers. Section II: Forty-four patients requiring IV cannulation before scheduled eye surgery. Interventions: Section I: Volunteers re ceived iontophoresis of lidocaine HCl 2% with epinephrine 1:100,000 fo r a total delivery current of 40 mA . min. Section II: Patients receiv ed iontophoresis for a total delivery current of 40 mA min of lidocain e HCl 2% with epinephrine 1:100,000 (active) or saline (control) immed iately before intravenous cannulation with a 20-gauge IV catheter. Maj or Outcome Measures: Section I: Venous blood plasma lidocaine levels, adverse events associated with iontophoresis. Section II: Patient and investigator assessment of analgesia, patient acceptance of iontophore sis, adverse events associated with iontophoresis. Results: Section I: No detectable levels of lidocaine were identified in any blood plasma sample. Adverse effects were minimal and transitory. Section II: Pain was decreased following lidocaine iontophoresis in comparison with co ntrols, as determined by the patients and investigators. Iontophoresis was well accepted by the patients. Adverse effects were minimal and t ransitory. Conclusions: Iontophoresis of lidocaine 2% with 1:100,000 e pinephrine for short delivery times does not lead to delivery of clini cally important systemic levels of lidocaine in healthy adults. Iontop horesis of lidocaine 2% with 1:100,000 epinephrine provides adequate s kin anesthesia for placement of peripheral small-gauge IV catheters.