Epileptic drugs will enhance the destruction of vitamin D making patients who are on anti-seizure medications at higher risk for developing vitamin D deficiency and osteomalacia or rickets. Measurement of 25-hydroxyvitamin D [25(OH)D] is important in patients on antiepileptic medications. Often twice as much vitamin D is required to maintain a blood level of 25(OH)D of > 30 ng/ml. Thus, 2,000-4,000 IU of vitamin D is usually needed. An alternative is to take 50,000 IU of vitamin D2 either once every week or once every two weeks depending on the serum 25-hydroxyvitamin D level. 
Epilepsy
