Effect of levetiracetam on the postmastectomy pain syndrome

Background and purpose: The aim of this randomized, double-blind, placebo-controlled, cross-over study was to test whether levetiracetam relieves the postmastectomy pain syndrome (PMPS). Methods: Postmastectomy pain syndrome was defined as pain of neuropathic character located in the area of the surgery and/or the ipsilateral arm. The inclusion criteria were: age more than 18 years, characteristic symptoms corresponding to PMPS more than 6 months after surgery for breast cancer, pain duration more than 3 months, peripheral nerve lesions confirmed by abnormal neurological and quantitative sensory tests, intensity of pain more than 4 on a numeric rating scale from 0 to 10 and pain present at least 4 days a week. Results: Forty-nine patients were screened for participation and 27 patients were included in the study. Twenty-five patients completed two treatment phases of 4 weeks duration with levetiracetam (3000 mg/day) and placebo. There was no difference in the rating of pain relief between treatment with levetiracetam (P = 0.83) and placebo nor when adjusted for possible period effect (P = 0.60). Analysis defining response as pain relief more than 4 on an eleven-point numeric rating scale showed no significant difference between treatment with levetiracetam and placebo (P = 1.00). Conclusions: Levetiracetam apparently does not relieve peripheral neuropathic pain in PMPS.