New treatment of lumbar disc herniation involving 5-hydroxytryptamine2A receptor inhibitor: a randomized controlled trial

Abstract

Serotonin or 5-hydroxytryptamine (5-HT) is a chemical mediator associated with nucleus pulposus-induced radiculopathy. Inhibition of 5-HT receptors may potentially alleviate symptoms in patients with lumbar disc herniation. This prospective randomized controlled study was performed to evaluate the efficacy of the 5-HT2A receptor inhibitor in the treatment of symptomatic lumbar disc herniation. Forty patients with sciatica due to L4-5 or L5-S1 disc herniation were randomly allocated to treatment with the 5-HT2A inhibitor (sarpogrelate 300 mg/day) or nonsteroidal antiinflammatory drugs (NSAIDs; diclofenac 75 mg/day). Low-back pain, leg pain, and numbness were evaluated using a visual analog scale (VAS) before and after a 2-week course of treatment. The patients received only allocated medicine during the 2-week regimen and were thereafter allowed to choose any treatment options depending on their residual symptoms. One-year clinical outcomes were assessed based on the rates of additional medical interventions. The mean VAS score improvements in the 5-HT2A and NSAID groups were 33 and 46% for low-back pain, 32 and 32% for leg pain, and 35 and 22% for leg numbness, respectively. After the 2-week regimen, no additional medical interventions were required in 50% of 5-HT2A-treated patients and 15% of those receiving NSAIDs. Epidural or nerve root block procedures were performed in 35% of the 5-HT2A group and 45% of the NSAID group. Surgery was required in 20% of the 5-HT2A group and 30% of the NSAID group patients. The current study provided evidence that the efficacy of the 5-HT2A inhibitor was comparable with that of NSAID therapy for lumbar disc herniation. The 5-HT2A inhibitor has the potential to alleviate symptoms in patients with lumbar disc herniation.