Four Cases of Suspected Levetiracetam-Induced Asymptomatic Rhabdomyolysis.

Rhabdomyolysis is a known side effect of levetiracetam. In general, a patient with rhabdomyolysis complains of muscle pain and swelling. Herein, we report four cases of asymptomatic levetiracetam-induced rhabdomyolysis. In all the four cases, the seizures resolved after more than five days. The patients received continuous fluid replacement from the time they were admitted to our hospital. However, serum creatine kinase (CK) levels continued to rise without symptoms consistent with rhabdomyolysis. The serum CK level improved rapidly when levetiracetam was replaced with lacosamide. Because levetiracetam occasionally causes asymptomatic rhabdomyolysis, routine blood tests should be performed after its initiation.