Influence of solar irradiation on vitamin D levels in children on anticonvulsant drugs

Acta Neurol Scand. 1989 Apr;79(4):296-9. doi: 10.1111/j.1600-0404.1989.tb03788.x.


Previous studies about the serum levels of vitamin D metabolites in epileptic patients have given conflicting results. We have investigated the influence of chronic anti-epileptic treatment on mineral metabolism in 17 ambulatory epileptic children who were studied for 2 seasons with high and low levels of solar radiation, respectively. No differences in serum calcium, phosphate or 1.25-dihydroxyvitamin D were observed between patients and control children. Patients also had normal levels of 25-hydroxyvitamin D [25(OH)D] in summer. However, serum 25(OH)D concentrations were lower in patients than in controls in winter months (12.6 +/- 1.4 versus 19.6 +/- 1.2 ng/ml, P less than 0.001). These findings point out the influence of the intensity of solar irradiation, and subsequently of vitamin D availability, on the effect of anticonvulsant drugs on vitamin D metabolism, and may help to explain the conflicting results of previous reports. Prophylactic vitamin D therapy should be considered when climatic conditions or patients' life styles do not allow an adequate exposure to sunlight.

MeSH terms

  • Adolescent
  • Anticonvulsants / pharmacology
  • Anticonvulsants / therapeutic use*
  • Child
  • Child, Preschool
  • Epilepsy / drug therapy
  • Epilepsy / metabolism*
  • Female
  • Humans
  • Male
  • Seasons*
  • Vitamin D / blood
  • Vitamin D / radiation effects*


  • Anticonvulsants
  • Vitamin D