This study was carried out to determine the efficacy of gabapentin in patients with radiculopathy. Fifty patients (32 women, 18 men) with lumbosciatalgia secondary to L-5 or S-1 radiculopathy were evaluated. MRI showed L4-5 and/or L-5-S-1 bulging and/or protrusion without significant spinal stenosis. Baseline assessments for each patient included a standard neurological examination and radiological investigation. The patients were randomly assigned into two groups: group 1 was treated with oral gabapentin from a total of 900 mg per day up a total of 3600 mg per day divided in 3 doses; group 2 received placebo for the 8-week trial period. In group 1 we observed statistically significant improvement in pain at rest (p < 0.001), motor function (p < 0.01), limitation of spinal flexion (p < 0.001), straight leg raising test (p < 0.001) and sensory function (p < 0.001). Stretch reflexes instead did not significantly change. In group 2 we observed significant improvement in all clinical parameters, muscle strength and stretch reflexes excluded. The results of group I were significantly better than those of group 2.