INTRODUCTIONIn patients with epilepsy, chronic therapy with conventional enzyme inducing antiepileptic drugs (EIAED's) causes abnormalities in calcium metabolism. These including hypocalcaemia, hypophosphatemia, elevated levels of serum alkaline phosphatase, serum parathyroid hormone and reduced serum levels of biologically active vitamin D metabolites. These changes cause radiologic evidence of rickets, and histological evidence of osteomalacia. [1][2][3][4] These patients are also at high risk for pathological fractures due to reduction in the bone mineral density. These EIAED's which include phenytoin, carbamazepine, primidone, phenobarbitone and benzodiazepines cause decrease in bone mineral density by hepatic induction of cytochrome P450 enzymes ABSTRACT Background: Objective of the study was to determine the Levetiracetam monotherapy effect on serum calcium and serum vitamin D levels in tertiary care hospital in Haryana, India. Methods: A total of 110 patients with epilepsy, were enrolled to the study for one year between April 2013 to August 2014. All male patients aged 15-60 years and premenopausal females with epilepsy were included in the study. The study was a interventional prospective study design. The antiepileptic drug levetiracetam was administered starting from a dose of 20 mg/kg and dose was titrated according to the clinical response. During the follow up period, the subjects were asked about the seizure frequency and other side effects. The patients were be subjected to questionnaires based proforma. Baseline investigations, Hemogram, renal and liver function tests, calcium, phosphate, vitamin D and bone mineral density and T scores were noted. All investigations were repeated after one year of levetiracetam monotherapy. Results: The mean age of onset of seizures in the study group was 23.22±6.62 years. 58% (n=29) were seizure free after 1 year of levetiracetam monotherapy, 28% patients had adequate control and 14% patients had poor control of their seizure episodes. There was an insignificant change in Hemoglobin, total leukocyte count, platelet count, renal parameters and Liver enzymes from baseline over a year of levetiracetam therapy. Serum calcium levels increased insignificantly from baseline levels of 9.68±0.59 mg/dl to 9.72±0.56mg/dl. Vitamin D levels increased from baseline of 39.35±14.91ng/ml to 39.84±14.07 ng/ml. Bone mineral density increased insignificantly from baseline of 0.92±0.13 g/cm 2 to 0.93±0.13 g/cm 2 . Conclusions: Present study has shown an overall beneficial effect on serum calcium, Vitamin D level, bone mineral density and T scores on DEXA scan.