A 64-year-old patient with symptomatic epilepsy developed thrombocytopenia during treatment with levetiracetam (LEV). As no other medical reason could be evaluated, a medication side effect was postulated. The only new drugs were valproic acid (since 3 weeks) and levetiracetam (since 3 days). After valproic acid medication was ended, thrombocytopenia did not improve and even worsened further. Finally levetiracetam administration was ended and trombocytopenia resolved rapidly and completely within few days.