Lidocaine patch treatment in patients with low back pain: results of an open-label, nonrandomized pilot study

This prospective, 6-week, multicenter, open-label, nonrandomized pilot study was designed to assess the effectiveness and safety of a lidocaine patch 5% in patients with low back pain (LBP). Patients with moderate to severe LBP, defined as acute/subacute (< 3 months, n = 21), short-term chronic (3-12 months, n = 33), or long-term chronic (> 12 months, n = 77), were recruited from 5 clinics; participants applied < or = 4 patches (560 cm total) once daily to area of maximal LBP as add-on treatment through week 2, with the option to taper concomitant analgesics during weeks 3-6. Scores on Brief Pain Inventory (BPI) were obtained at weeks 2 and 6. Safety analyses included reports of adverse events (AEs) and skin sensitivity to pinprick/light touch. Significant improvements in average daily pain intensity on the BPI were noted at weeks 2 and 6 (P < or = 0.001). Significant improvements in pain interference with quality of life (QOL) were noted for all BPI measures of QOL at weeks 2 and 6 for the acute/subacute (P < or = 0.007) and long-term chronic LBP groups (P < 0.0001) and for 5 of 7 BPI measures for the short-term chronic LBP group (P < or = 0.042). Fifty-eight percent of patients reported being "satisfied" or "very satisfied" with treatment. The lidocaine patch was well tolerated. Most common AEs were dizziness and rash (n = 5, 3.8%), and most AEs (80%) were mild to moderate in intensity. Significant improvement in pain intensity and QOL in this cohort of LBP patients was noted during treatment with the lidocaine patch 5%. Controlled clinical trials are warranted.