Effects of levetiracetam on chronic pain in multiple sclerosis: results of a pilot, randomized, placebo-controlled study

Background and purpose:  Central neuropathic pain (CNP) is a prevalent and distressing symptom in patients with multiple sclerosis (MS). The anticonvulsant levetiracetam (LEV) has been shown to be efficacious in some types of CNP, but its efficacy in MS-related CNP has not been confirmed.
Methods:  To investigate the tolerability and potential effects of LEV against CNP in MS subjects, we performed a single-center, prospective, randomized, single-blind, placebo-controlled study in twenty patients with MS and CNP. Outcomes before and during the 3-month study were assessed using validated measures of pain, depression, disability and quality of life.
Results:  The medication was well tolerated and analysis revealed a significant difference between the LEV and placebo arm in all study outcomes related to pain (mean pain intensity score, mean pain difference, percentage of patients with a clinically significant pain reduction). Furthermore, the individual quality of life rating improved in treated patients, showing a significant correlation with pain reduction.
Conclusions:  These findings suggest that further studies with larger samples of patients be carried out in order to confirm the efficacy of LEV in MS-related CNP population.