Patients treated with the anti-epileptic drug Valproic Acid are more susceptible to decreased bone mass, according to a report published in the journal Neurology.
Researchers studied 40 people with epilepsy who have been taking valproic acid as their sole anti-epileptic drug (AED) for over a year. Sixty per cent of the participants in the group had a reduced bone mineral density (BMD), the measure of the amount of calcium in the bone, with around a quarter of the group showing signs of osteoporosis.
Previous studies have shown that several AEDs caused the formation of enzymes that reduced levels of vitamin D and resulted in the reduction of the BMD. However, as valproic acid does not produce these enzymes, the authors, led by Dr Yoshihiro Sato of the Hirosaki University School of Medicine, were surprised at the level of BMD reduction in the group.
Dr Sato commented that regular measurements of bone density should be performed on patients who are taking valproic acid for their epilepsy.