Gabapentin-induced myopathy in 2 patients on short daily hemodialysis.

Gabapentin is an antiepileptic medication that also has been used for restless legs syndrome. The mechanism of action is unknown. The most commonly reported adverse effects of this medication include somnolence, dizziness, ataxia, fatigue, nystagmus, and tremor. Myalgia has been reported in 2% of gabapentin users compared with 1.9% of patients in placebo-controlled add-on trials. Two patients on short daily hemodialysis therapy developed neuromuscular symptoms and an elevation in creatine kinase levels after starting gabapentin therapy. To our knowledge, this is the first case report of an increase in creatine kinase level after the administration of gabapentin.