In another lidocaine dose-response study an infusion of 500 mg of lidocaine over one hour in 13 patients with neuropathic chronic pain (6) resulted in plasma levels of 2.43 +/- 1.01 mcg/mL at the initial onset of analgesia. This corresponds to infusion rates of approximately 6-7 mg/kg/hr of lidocaine (no bolus). The amount of lidocaine used at the onset of analgesia was 123+/-55 mg over ~ 9-20 minutes. Complete analgesia was reported in 10 out 13 patients with corresponding plasma levels of 3.79+/- 1.00 mcg/mL with a total lidocaine dose of ~ 375 +/- 23mg over 36-54 minutes. In 3 patients there was a significant reduction in pain but no complete analgesia. Light-headedness at some time during infusion was reported in 6 out of 13 patients and their lidocaine levels ranged from 0.9 to 3.08 mcg/mL. At no time did the infusion need to be adjusted because of subjective complaints of toxicity.