A Case of Levetiracetam-Triggered Rhabdomyolysis Reversed by Drug Cessation

Levetiracetam is a commonly used anticonvulsant medication, usually a first-line drug in the treatment of generalized and partial tonic-clonic seizures. Levetiracetam is well-tolerated in most instances, with common side effects including somnolence, dizziness, and headache. Rhabdomyolysis is a rare but serious side effect that can occur. Rhabdomyolysis is caused by the breakdown of skeletal muscle fibers with creatine kinase (CK) and myoglobin release into the circulation and may be a potentially life-threatening disorder if not identified and treated early. Here, we present the case of a 34-year-old male who was admitted for two episodes of tonic-clonic seizures. Initial admission labs before the first dose of levetiracetam showed a CK level of 351 U/L. Post-admission, he was started on 1 g of intravenous levetiracetam. Subsequently, his CK levels also increased exponentially in conjunction with aberrations in his liver function tests (LFTs). Once levetiracetam was discontinued and carbamazepine (another anticonvulsant medication in a different class) was commenced, his CK and LFTs further improved, suggestive of levetiracetam-induced rhabdomyolysis. The patient's CK level was 351 U/L at presentation and rose to over 22,000 U/L by day four after starting levetiracetam. Following a change in medication, the level decreased to 3,591 U/L by the time of discharge. This case highlights the importance of closely monitoring CK in levetiracetam-treated patients to facilitate early detection and management in the case of rhabdomyolysis. If elevated CK is detected, levetiracetam withdrawal and initiation of a different anticonvulsant should be strongly considered.