Evaluation of efficacy and tolerability of eperisone and thiocolchicoside in treatment of low back pain associated with muscle spasm: An open label, prospective, randomized controlled trial

Background: Low back pain has a high prevalence in adult population. Because of reflex muscle spasm, muscle relaxants are frequently used either alone or in combination with analgesics. Eperisone inhibits voltage gated sodium channels in brain stem and Thiocolchicoside acts via GABA-mediated mechanism to relax muscle spasm and relieves pain.Methods: This was a prospective; open labeled, randomized, two-arm, parallel group, controlled, clinical trial. 113 patients were randomised to two groups. Patients in group A received Tablet Eperisone 100 mg whereas patients in group B received Tablet Thiocolchicoside 8 mg for seven days along with Tablet Paracetamol 500 mg. The outcome measures of trial were the improvement in finger to floor distance (FFD) and pain in lumbar region, relief of spasm and tenderness of paravertebral muscles on day 4 and 7.Results: At the end of the study FFD reduced by 18 cm in group A (p < 0.0001*) and 17.36 cm in group B (p<0.0001*) from baseline. Mean score of pain on day 7 reduced by 5.64 scale in group A as compared to 5.42 scale in group B (p<0.0001* in both groups). Paravertebral tenderness reduced by 92.6% in group A and 94.6% in group B at the end of the trial. On day 7, the spasm relief was 87% in group A and 88% in group B.Conclusions: Eperisone is an effective muscle relaxant with equivalent efficacy compared to Thiocolchicoside, and has a better tolerability in treatment of low back pain with muscle spasm