Lamotrigine is a newer anti-epileptic drug for adjunctive treatment of refractory epilepsy, partial seizures, generalized tonic-clonic seizures, and bipolar disorder. Lamotrigine overdose causes serious central nervous and cardiovascular problems, but reports are uncommon. Few lamotrigine overdoses have been described because anti-epileptic drug use is limited and usually used with combination of other anti-epileptic drugs. In addition, most patients visit emergency departments with multi-drug overdoses, so few cases of lamotrigine poisoning alone exist. We had a female patient visit our emergency department a couple of hours after a lamotrigine overdose treated with intravenous hydration and urine alkalization by NaHCO3. She recovered successfully without any evidence of renal injury. However, she developed profound rhabdomyolysis, a previously unreported complication of this medication. We suggest that serial creatine kinase levels should be measured after lamotrigine poisoning.