8% Lidocaine Pump Spray Relieves Pain Associated With Peripheral Blood Flow Disorders

Abstract

It is often difficult to reduce pain associated with peripheral blood flow disorders (PBFD) using standard analgesics. We assessed the analgesic effects of a metered-dose 8% lidocaine in patients with PBFD. Twenty-four patients with PBFD-related pain were enrolled in this double-blind placebo-controlled crossover study. Patients were randomized to receive either 8% lidocaine or saline on the painful site with a metered-dose spray. After a 3-day period, patients were crossed over to receive the alternative treatment. Pain was assessed with a visual analog scale (VAS) before and 15 minutes after the treatment. Patients were also asked to record the time at which pain appeared again. The blood concentration of lidocaine was measured at 15, 30, and 60 minutes after lidocaine application. There were no significant differences in VAS before treatment between the placebo and lidocaine treatments. However, lidocaine significantly decreased VAS at rest from 5.5+/-3.1 cm (mean+/-SD) to 0.6+/-0.9 cm and on movement from 8.4+/-2.0 cm to 1.7+/-1.7 cm, resulting in a significant difference between the 2 sprays. The median time to recurrence of pain was 3 hours. The blood concentration of lidocaine was less than 0.3 microg/mL in all patients. A metered-dose 8% lidocaine pump spray produced prompt analgesia in patients with PBFD-related pain without severe side effects.