Low therapeutic index of established antiepileptic drugs (AEDs) coupled with better understanding of the pathophysiology of seizure has encouraged the development of several novel AEDs. The conventional antiepileptics like phenytoin, phenobarbitone, valproate and carbamazepine and newer antiepileptics like levetiracetam. are used for epilepsy. AEDs induce potentially toxic effects over a period of time which remains undetermined over very long time. Earlier studies in this regard, states uneven results about hematological (Hb%, blood cell count etc.) toxicity of AEDs.

Epilepsy is a chronic neurologic disease that is considered the most common neurological diseases in the world and comes third after cerebrovascular and Alzheimer's disease. Epilepsy is a disorder characterized by a long-term tendency to cause epileptic seizures due to abnormal electrical activity in the brain with neurological, cognitive, psychological and social consequences . However, it is not a single disease entity but it is a collection of different kinds of seizures resulting from several mechanisms and different cause. The aim of epilepsy management is complete seizures cessation and maintenance of a good quality of life, which is affected not only by the epileptic attacks but also by the adverse effect of the drugs used .Levetiracetam (LEV) is a relatively new, broad-spectrum AED that has seen extensive use during recent years . Its mechanism of action is not completely known, but differs from those of other AEDs. LEV is described as being well tolerated, and the most common adverse effects are generally mild . Studies evaluating the effect of levetiracetam on hematological parameters have reported a spectrum of hematological abnormalities that ranges from mild thrombocytopenia or neutropenia to anemia, red cell aplasia, until bone marrow failure. Fortunately, potentially fatal hematological disorders such as aplastic anemia are very rare.

Inclusion Criteria: Adult Epileptic patients of both genders aged >18 years on mono-therapy of levetiracetam anti-epileptic drug treatment for at least six months.

Exclusion Criteria:

1. Patients were on treatment for less than six months.
2. Patients had other conditions besides epilepsy that could affect blood parameters.
3. patients on treatment with other antiepileptic medications besides levetiracetam.

Based on determining the main outcome variable, The estimated minimum required sample size is 45 patients. The sample size was calculated using Epi-info version 7 software, based on the following assumptions: Main outcome variable is to investigate hematological changes in adult patients with epilepsy who were treated with levetiracetam as monotherapy. Based on previous studies [8] the percentage of patients who their hemoglobin fell below 10g/dl while taking Levetiracetam was 8%, and based on the percentage confidence limits of 5% and a Confidence level=80%