Epilepsy is a disease of the brain characterized by an enduring predisposition to generate epileptic seizures and by the neurobiologic, cognitive, psychological, and social consequences of this condition, it is one of the most common neurological illnesses that affect individuals of any age and ethnicity(1). Epilepsy is the most frequent chronic neurologic 
condition in childhood that affects 0.5: 1.0 % of children globally(2). About 30% of childhood epilepsy is idiopathic(3)
Vitamin D3 (25-hydroxy vitamin D3) have an important role in human health, it plays a pivotal role in calcium and bone metabolism (by increasing the absorption of calcium and phosphorus in the intestine and inhibiting the secretion of parathyroid hormone), therefore, its deficiency may cause rickets, osteopenia, and osteoporosis(4). In addition, vitamin D plays an important role in brain development and behavior as well (it is involved in neuroprotection, brain cell proliferation and differentiation)(5). It is also has been reported that vitamin D deficiency has been associated with an increased risk of many diseases such as cancers, autoimmune diseases, hypertension, and infectious diseases(6)..
Epileptic children need long-term anticonvulsant therapy, therefore, they have a higher risk of adverse effects(6). A large body of evidence since 1960 indicates that antiepileptic drugs (AEDs) impact bone metabolism negatively leading to impaired bone quality and increased risk of fractures(7). Recently, it has been reported that children with epilepsy who were treated with AEDs are at increased risk of poor bone health and they often have additional risk factors for vitamin D 
deficiency(8). This observation lead to extensive research on the interaction between antiepileptic drugs and vitamin D(9)